Temperature flap servo motor - no target value? (V159, right side)

Due to certain circumstances (negative temperatures and no heating for the passenger seat), here's a question regarding the "comfort/climate" area:

The temperature control for the passenger side has been malfunctioning for quite some time. (Error message is shown below, and there are corresponding "clattering" noises in the dashboard, as if there's an animal living inside...)

My question today concerns the actuator diagnosis for the temperature flap control motor on the right side (V159).

(I'll address the issue with the servo motor for the back pressure valve - V71, see also below - later.) For today's task, this component is tentatively considered irrelevant to my analysis, as the actuator motor showed no abnormalities during the actuator diagnostics.

If I have understood and observed correctly (see also the image below), then in the actuator diagnosis, the actual value is displayed on the far left, and to the right of it, the target value alternates between the end values, which are displayed as the upper and lower learning values for the basic setting in the two fields on the far right.

When functioning correctly, the actual value (on the far left) briefly matches the setpoint value (displayed directly to the right) after the setpoint value is changed.

My question, which arises from the image attached below: How should I interpret the fact that only one actual value is displayed, but neither a target value nor the corresponding specifications for the upper and lower limits?

Before I start disassembling the actuator, it would be very helpful for me to have a clearer understanding of the symptoms.

First, I thought it might be a cable connection problem - which I will, of course, also check.

- Are there any indicators, besides a physical inspection, that can be read out using VCDS?
- For example, does it have any significance that the first error message at the bottom ("01810 - Temperature control valve actuator, right, V159") is followed by a blank line in the next line ("000 - - ")?
- but for the error below, "01274 - Servo motor for pressure relief valve, V71", the frequency is "000 - - - Intermittent"? (Even though the error frequency seems similar.)
- And what should I think about the fact that there is absolutely nothing listed in the coding for the Climatronic - is this normal?

(I took over the car from a work colleague - the original buyer - who definitely didn't change anything on it.) I've somewhat dismissed the theory of a cable connection problem - wouldn't there be no "actual value" in that case? (Of course, there can also be connection problems sometimes, but this seems somewhat unlikely to me.)

Quote:

What do professionals interpret from such a configuration (no "actual value," no final values)? Is the axis of the servo motor misaligned, which is why no learning values can be determined during the initial setup, and therefore no actual value can be obtained? On the other hand, learning values seem to be present; here are the values for "G221 potentiometer for the temperature control flap servo motor, right side" from the measurement data blocks (below are the values for the driver's side, G220): Address 08: Climate Control/Heating Module (3C0 907 044 AJ) 12:40:57 26.0 Potentiometer (G221) Actual value 227.0 Setpoint (G221) 27.0 Learning value (G221) (cooling) 227.0 Learning value (G221) (Heating) "Die Sonne scheint hell, und die Vögel zwitschern fröhlich. Es ist ein wunderschöner Tag, um spazieren zu gehen oder ein Picknick im Park zu machen. Viele Menschen genießen das gute Wetter und verbringen Zeit im Freien." Address 08: Climate Control/Heater (3C0 907 044 AJ) 12:40:36 226.0 Potentiometer (G220) Actual value.

228.0 Setpoint (G220)
30.0 Learning Value (G220) (Cooling)
228.0 Learning value (G220) (Heating)
The upper and lower learning values for G221 ("cooling" or "heating" of the passenger side) are now in place.

Compared to the temperature flap on the left side (potentiometer G220, as seen in the second group of values), I notice that the target temperature on the passenger side (G221) is not being reached (actual temperature is 26, while the target is 227), whereas it is being reached on the driver's side with G220 (actual temperature is 226, while the target is 228).

The most important thing for me, however, is the question that arises from the image below:

Quote:

What do you think about the fact that, in actuator diagnostics, only an actual value is displayed, but neither a target value nor the learning values for the upper and lower limits? If anyone has any ideas, I would be grateful. I am very happy with the help I have received in this forum so far, and I am also trying to contribute in my own way, just as I am learning and understanding things. Here are the error values: Address 08: Climate Control/Heating Module. Label file: DRV\3C0-907-044.lbl Control unit part number: 3C0 907 044 AJ Hardware: 3C0 907 044 AJ Component and/or version: ClimatronicPQ46 050 0505 Encoding: Operating number: WSC 00000 000 00000 VCID: 69DE70F240E7BB0E3D-803C 2 error codes found: 01810 - Temperature flap servo motor, right side (V159) 000 - - Environmental conditions: Error status: 01100000 Error priority: 3. Error frequency: 5 Lost Count: 96 Mileage: 208,645 km Time: 0 Date: 2018.02.06 Time: 13:29:50 01274 - Actuator for pressure relief valve (V71)

000 - - - Sporadically http://wiki.ross-tech.com/wiki/index.php/01809
Environmental conditions:
Error status: 00110000
Error priority: 3.
Error frequency: 3
Lost Count: 134
Mileage: 208,645 km
Time: 0
Date: 2018.02.06
Time: 13:29:50
http://wiki.ross-tech.com/wiki/index.php/01274
"No entry found in the Ross-Tech Wiki for error code 01810."
vgl. aber driver's side, fault code 01809:
and pressure relief valve, error code 01274:

Hello,

Quote:

What is your opinion on the fact that the actuator diagnosis only displays an actual value, but neither a target value nor the learned values for the upper and lower limits?

In actuator diagnostics, the actuators are driven to defined values (not regulated) .

Regarding your issues: Either the motors in the valves are worn out or dirty, but often the valve itself is the problem, being difficult to operate. Unfortunately, it's often difficult to access the actuators/valves.
I've gotten into the habit of occasionally running through all the settings and positions of the Climatronic system to ensure that nothing gets stuck.
It helped for the last 100,000 km, but before that, a valve would occasionally get stuck.

Best regards, Rainer.

Hi,

I am also just an interested amateur, and therefore can only offer guesses, which you would need to check for plausibility.

The most common causes of failure in servo motors are worn or contaminated potentiometers. These lead to either...
A) If no valid current position can be detected --> error message.
B) A false current position is detected --> Faulty control.
C) As a consequence of B), the final value is repeatedly overwritten, and the gears are over-rotated.

Phaidros wrote:

How should I interpret the fact that only one actual value is displayed, but neither a target value nor the corresponding specifications for the upper and lower limits?

I suspect that Poti did not establish contact during the initialization process. Therefore, the initialization failed, and an error was logged. "Consequently, the upper and lower limit values are missing, and due to an active error, there is no longer a target value (the error has been detected, and the valve should therefore no longer move -> no target value)."

Phaidros wrote:

What do professionals read from such a configuration (no "current value," no final values)?

Almost as before. However, additionally: In none of the current readings does the potentiometer appear to be making contact.

In short: I find the observed issues with a faulty servo motor to be plausible, and I expect that you only need to replace it.

Greetings.
Guste.

Thank you for the answers.

Rainer:

Quote:

However, the corresponding valve is often difficult to operate

.
Is it true that I can only access the flaps by removing the dashboard trim? (If I understand correctly, the temperature control flap actuator on the right side, V159, is somewhat easier to reach, located behind the center console trim to the left of the glove compartment.)

Quote:

From time to time, it's a good idea to cycle through all the settings and positions of the Climatronic system to ensure that nothing gets stuck

.
Simply through the control buttons of the climate control system - or through actuator diagnostics?

Quote:

Helped for the last 100,000 km, but before that, a valve would occasionally get stuck.

A good tip for prevention - thank you. And did the hinged flap detach itself again due to the aforementioned "mobilization of arthritic elements"?
I don't really have much hope, so I'll probably focus on troubleshooting and examining the stepper motor and potentiometer.

What makes me suspicious is that there isn't even a "target value" defined for this actuator. (But maybe, as Guste suspects, that's normal for a defective actuator or potentiometer.)

Guste:

Quote:

I find the observed issues with a faulty actuator plausible, and I expect that you only need to replace it.

I suppose I'll get started on that now.

I'm going to watch a few videos first on how to remove the V159 actuator. According to the repair manual, it's quite a few steps. Above all, I want to see if it's really necessary to remove all of the components listed.

Quote:

Remove the glove compartment, remove the lower trim panel of the center console, remove the heater unit shield, remove the right footwell vent, remove the central control unit for the comfort system J393 and the control unit for cornering light and headlight range control J745, then unscrew the support from the aggregate carrier and rotate it to the left until the mounting screws and the temperature flap actuator on the right side (V159) are accessible.

I have already watched this video once (without understanding the language): https://www.youtube.com/watch?v=PeJjX9e2Gmo

I'll try to see if the motor actually moves anything before I start disassembling it. (Surprisingly, something is constantly rattling in the climate control system, as if it's constantly trying to adjust something.) It's actually quite remarkable that there isn't even a target value specified.

Thank you again for the helpful information so far.

Here's another video as an addition (again, the audio isn't much help to me in this one...).

At 4 minutes and 51 seconds, you can see how the silver bracket (above the vertical support) obscures the mounting screws of the actuator motor.

However, according to VW not - as shown in this video - is the bracket unscrewed from the support (because the bracket is screwed to the support from the back), but rather the support itself is loosened at the top and bottom, and then rotated to the left, so that the mounting screws of the actuator motor become accessible.

https://www.youtube.com/watch?v=L7nBa_FRJaU

The author of the video generally operates more in "experimental" mode rather than "expert" mode (although I just wanted to see what it looks like).

The image above (in my original question) shows the missing target value for the temperature control flap servo motor on the right side, V159.

Here's a comparison image of the actuator diagnosis for the throttle motor of the secondary air control valve V113 (with the connector cable disconnected). This actuator is relatively easy to access, as it is located directly behind the glove compartment.

When the connection cable is disconnected, the setpoint value - shown in the second position - changes as expected between the end values (which are also displayed to the right).

Only the actual value on the far left (in image 255) remains static (since the servo motor is not connected and the potentiometer is not being moved).

This is a completely different behavior compared to the problem I'm having with the temperature flap control motor on the right side (V159): Therefore, a cable issue, as initially suspected, does not seem to be the cause of the problem.

Perhaps the engine control unit has actually "disabled" the position sensor V159 (and is no longer communicating with it) because the engine is faulty or the final values could not be determined - for example, due to a problem with the potentiometer.

This is just a preliminary update - more to come soon.

Here are a few more photos:

Image 1: View of the expanded glove compartment: On the left in the background (with a highly reflective label) is the temperature control flap actuator on the right (V159). To the right, above the blower fan housing, the (closed) recirculation flap is visible. Directly to the left and vertically adjacent is the actuator motor for the air control flap (V113) with a dark blue connector.

To remove the glove compartment for expansion, only 3 screws at the bottom and 4 screws at the top were loosened. It was then simply placed in the passenger footwell (with the connectors still attached). When disassembling, be sure to use a small screwdriver to release the locking mechanism at the bottom (near the air vent) as the final step.

Image 2: Overall view of the temperature control flap servo motor on the right side, V159 (which can be recognized by the highly reflective label in the background). It is obscured by a metal bracket and a control unit located in front of it. In the upper right corner of the image, you can see the blue connector of the secondary air flap control motor (V113).

Image 3: A closer view of the temperature flap control motor (V159) located in the background on the right side, and the control unit for cornering light and headlight range adjustment (5M0 907 357) located in front of it.

Image 4: Detail view of the servo motor for the right temperature flap (V159): 3C0.907.511.B

Figure 5: Larger view of the recirculation flap and the attached actuator for the recirculation flap (V113) with the blue connector.

Figure 6: Detail view of the recirculation flap servo motor (V113): 3C1.907.511.B

My plan is to first remove the functional recirculation flap actuator (V113), examine it, and take measurements. Then, I will remove the (problematic) V159 actuator for the right-hand temperature flap.

If I'm interpreting this correctly, both units are identical in terms of their motor and housing. The V113 connects directly to the axis of the recirculation flap, while the V159 has an additional lever attached. However, I believe the differences in the prefix ("3C1" versus "3C0") are probably not really significant, as those usually contain the supplier code or revision information.

I would then test the stepper motor (V113) for the recirculation flap (V113) on the right-hand temperature control flap to get closer to the source of the problem (before buying anything), especially since the V113 is very easy to remove as it is simply clipped in place.

Phaidros wrote:

When the connection cable is disconnected, the target value (...) changes as intended (...)

Perhaps the engine control unit has actually "deactivated" (and is no longer addressing) the position sensor V159 because the engine is defective or the final values (...) could not be determined.[/quote]
I would also say that the missing target value is due to the identified permanent error and the previously undetermined final value.

Have you ever disconnected the recirculation flap and disconnected the battery for a short time?
Then, the end-of-line detection would have to fail when the ignition is turned on, and the target value should also be missing. Then you would be absolutely certain.

By swapping the servo motors, you would have gained this insight (and even more), of course.

Best regards,
Guste.

Hello Guste, thank you for your feedback and the ideas.

I myself had also devised a test to examine the theory that "the failure to reach the target value is due to the inability to learn the final values."

And specifically like this:

- Removed the cables from the actuator motor of the air flap V113. (I had already removed this for the planned comparison, so this was already done.)
- Initial setup performed using a diagnostic device.
- Idea: End positions cannot then be learned successfully, because there is no feedback from the positioning motor unit (since it is not connected).
- Expectation: If the theory mentioned above is correct, then there should be neither end values nor a target value for the V113 recirculation flap.

Result: see image.

It now looks exactly like the problematic servo motor for the temperature flap on the right side (V159). See the Screenshot in the image at the very top of the original question.

Conclusion: If no end values can be determined for a servo motor during the initial setup ("basic setting" or via the control panel), it will no longer be activated (no "target value") as a result.

Therefore, there is a lot of evidence to support our theory (and that, for example, the motor itself or the potentiometer in the control unit V159 is defective).

However, I have to retract my previous statement that it couldn't be the cable (because, theoretically, it still could be, even though I consider it very unlikely).

I will report on the further progress later. In the meantime, best regards.

Current score:

I already tested the replacement stepper motor for the right-hand temperature flap (V159) by connecting it (which required quite a bit of disassembly) and calibrated the end positions.

Image 1: Now, there is also a target value present, which is 28 (in the second position, to the right of which are the final values), and the motor is in the final position of 28 (the actual value is shown on the far left of the image).
Image 2: Here is the actuator motor during the actuator diagnosis, at the other extreme position (the actual value on the far left is 219).
Figure 3: During the actuator diagnosis, the control arm (see also Figure 5) moves back and forth between its endpoints until the next diagnostic point is called up. Here, in a central position (current value 128)).

Image 4: Photo of the connected (but not yet installed) temperature control valve actuator on the right side (V159) in the lower end position (at value 2.
Figure 5: Motor V159 in the middle position (which corresponds to approximately the value shown in Figure 3).
Figure 6: Motor for the temperature flap on the passenger side is now set to the other, upper end value (actual value 219).

The old motor, which has not yet been removed, can be seen in the background.

Problem:
The control unit for the cornering light and headlight leveling, which is mounted above the actuator motor and covers it (see image 3 in the post from the 14th). The upper part (February) is fastened with two screws, but the lower one is not accessible.

The VW repair manual only states the following:

Quote:

Loosen and remove the mounting screws -arrows- and detach the control unit for turn signals and headlight range adjustment - J745 - -1-.

Amazing.

Perhaps I can move the bracket, which needs to be loosened and repositioned anyway (because it obstructs one of the motor's screws), far enough so that the lower screw of the control unit for cornering lights and headlight range adjustment also becomes accessible.

For those who already know all of this, my contribution is probably less exciting (and perhaps too detailed).

But I also write more for those who are still looking for help (the others already know ). Okay, hier ist die Übersetzung:

"And please translate the following text from German to English. Provide only the translation, no explanations. And please make sure the context is understandable from the post itself (even if the reader hasn't read all the previous posts in the discussion)."

First, the good news: Replacing the V159 stepper motor for the temperature flap on the passenger side is actually possible - and it has been successfully completed: warm air is now flowing from the vents again (which is important given the current temperatures of up to -5 degrees), and the error messages have disappeared - as has the noise like squirrels in the dashboard...

See the video "Programming the V159 stepper motor for the temperature flap on the passenger side" below for a look at the adjustment function. (By the way: right is the 'high' position, left is the 'low' position).

Incidentally, the (black) arm of the actuator is very easily attached to the (white) arm of the valve actuator: before installation, slightly rotate the actuator unit so that the actuator arm of the motor and the arm of the valve actuator (shown in black and white in the image) align with the recesses. (Once installed, they cannot "disengage" because the openings will no longer be in a position where they can be separated.)

It is, incidentally, irrelevant in which position the (black) actuator arm of the actuator unit is located before installation: simply move the (white) arm of the valve actuator to the appropriate position. (Again: the entire actuator housing - not the arm! - must first be rotated during installation in order to be able to attach the actuator arm to the valve actuator.)

The unfavorable news (to put it very mildly) for all those who are reading this because they still have it ahead of them: very unpleasant work...

I probably could do it much faster the second time, but even then: it would involve significant contortions due to very difficult-to-reach screws.

Furthermore, all the videos I've seen on internet platforms get it wrong (more on that below), because it actually works exactly as described in the VW repair manual:

Quote:

Unscrew the upper and lower screws of the support... Turn the support to the left until the mounting screws and the temperature flap V159 servo motor are accessible.

That sounds too simple to be true - and of course, it isn't: more on that shortly. Here are the images:

Image 1: Replacement of the temperature control valve actuator on the right side (visible on the right in the background, with the white "1" upside down below it).
Image 2: To access the V159 motor, the metal support visible in the background must be unscrewed at the top and bottom and shifted to the left.
Image 3: Close-up view of the metal support

that needs to be unscrewed (from the top and bottom). The problem with the metal support is:

- One of the two mounting screws at the top is partially obscured by a support plate (which is not mentioned in the repair manual) and is therefore extremely difficult to unscrew.
- The support itself is screwed in at a third location, which the repair manual does not mention, namely to the cover, which is located, in essence, in the lower left corner of the recess for the glove compartment.
- The cable harnesses attached to the support further restrict the support's mobility.
- Even after removing the three points mentioned above (and the two screws at the bottom of the bracket), the bracket can only be moved with extreme difficulty (and very little).

The control unit for the lights (in image 1 on the left) is located on a cover plate, which - as visible in the video and in image 1 between the control unit and the actuator motor - covers the two left screws of the actuator motor assembly.

This cover plate does not need to be removed (all the videos I've seen make this mistake) - by the way, neither does the control unit for the lights, but the cover plate is attached to the bracket and needs to be moved to the left - with some effort...! - so far to the left that the two left screws of the actuator unit V159 are accessible (more or less, with maximum contortions).

Why am I writing this in such detail? To spare at least parts of my ordeal to someone who is about to experience something similar...

Here, for the sake of completeness, is a list of the (seven) actuators installed in my vehicle for the valve controls of the heating/air conditioning system.

This refers to a Passat Variant B6 (3C5) from mid-2006. Later, minor modifications were made to this model, for example, the described issue with the support was somewhat mitigated for vehicles manufactured from calendar week 45/08 onwards.

I am also including the numbering of the corresponding potentiometers (each in parentheses, starting with "G" for "geber"), as this is required to read the values in real-time in the measurement blocks of the climate and heating electronics (address 0. Tip: Use the "Advanced Measurements" view for the best overview.

Overview:

Actuator motor for the back pressure valve: V71 (G113)
Actuator for the air recirculation flap: V113 (G143)

Actuator for the center vent: V70 (G112)
Defrost flap actuator motor: V107 (G135)

Temperature flap control motor, left side: V158 (G220)
Temperature flap control motor, right side : V159 (G221) .

Actuator motor for the indirect ventilation flap: V213 (G330). The

boost pressure and recirculation flaps are located "in front of" the glove compartment (when viewed from the inside), while the remaining actuator motors are very difficult to access, being positioned due to their function around the air distribution box (located at the front, in the center of the vehicle, behind the audio system).

Note: The stepper motor for the air intake flap (V113) with the potentiometer (G143) is only installed in the Passat models from 2006 up to week 21/07; afterwards, a combined stepper motor "V425" was installed, which combines the air intake flap with the back pressure flap (identified as "Stepper motor for fresh air/recirculated air back pressure flap" with potentiometer G644).

Function

:
V71 Pressure Relief Valve: Limits the intake opening at higher speeds (so that the air intake remains relatively constant) and closes it (or almost) during recirculation operation.
Recirculation flap V113: Opens in recirculation mode, allowing air to be drawn in from the vehicle's interior (behind the glove compartment).

Central valve V70: Controls the air distribution between the bottom and the top.
Defrost flap V107: Sends air directly to the windshield.

Temperature flap, left, V158: for temperature control, driver's side.
Temperature flap, right, V159: for temperature control, passenger side.

Flap for indirect ventilation V213

: for "upward" air distribution (see also the note in the next paragraph)An observation: The "Air distribution up" button on the Climatronic control unit actually directs the air not to the window (as I naively assumed "from before"), but to the outlet of the "indirect ventilation" located at the top center of the dashboard. The "Defrost" button is responsible for directly directing airflow to the windshield (which, in my case, also automatically activates the windshield heating).

Repair manualshttps://erwin.volkswagen.de: I used the repair manuals "Heating and Air Conditioning" (K0059020500 for CC 2010, CC 2012, Passat 2006, Passat CC 2009, Passat Variant 2006, edition 06.2016), "Body Assembly Work - Interior" (K0059020100), and "Electrical System" (K0059020000), which I obtained through a very affordable subscription (for one hour) to the online VW information portal at .

Thank you for your detailed description.

Then all that's left for me to do is: 1) Pray that my servo motor never breaks.
2) If the first approach fails: Remind me of your contribution and refer to this text for more information.

Greetings.
Guste.

Hello Guste,

Next time, it will definitely be easier - but it was the first time...

Here (in the picture below) is, as already mentioned in other posts, the internal workings of the defective temperature control unit 3C0 907 511 B for the right-hand temperature flap (V159).

I haven't opened anything beyond the casing yet, so a more detailed analysis will come later.

If it were only the motor, the solution would be simple (and very inexpensive: €0.95 including VAT, plus shipping). Shipping...):

BOSCH DC Motor 1 397 220 467 ("High-performance brand-name DC motor with interbronze plain bearings and a plastic worm shaft")

Technical Specifications:

Quote:

Operating voltage: 3...12 V- Idle current consumption: 20 mA. Power consumption: max. 0.18 A. Power: max. 1 W Idle speed: 3200 RPM. Maximum speed: 1600 RPM. Torque at maximum load: 5.7 mNm. Wave dimensions (length x diameter): 12 x 2 mm. Motor dimensions without shaft (length x diameter): 35x24.5 mm

Source (and product photo): https://www.pollin.de/p/gleichstrommotor-bosch-1397220467-310657

I might upload a few more detailed photos (and before/after shots) later.

Right now, I'm not entirely sure (and it's not that important to me), whether the potentiometers in all those control units for the different valves are the same? (Perhaps they are different, corresponding to different adjustment ranges - but maybe the adjustment range is the same for all of them.)

I didn't open either the (used) replacement part nor the original part for the recirculation flap for comparison. (I didn't want to take any risks.)

Best regards until next time.

Here are more views of the individual unit that was removed from the original vehicle due to a defect:

Image 1: The temperature control valve unit V159 for the right side, VW product number 3C0 907 511 B, is identified by a label as being from DENSO (CZ), with DENSO part number 116880-2900.

Image 2, label peeled off: The part number 3C0 907 511 B (or at least its base) is manufactured by BOSCH as 0 132 801 363. (Interesting detail on the side: A DENSO product number CZ 116880-2872 is also printed on the label.)

Image 3: When they are DENSO, the Stellarme (here, the temperature control valve V159 3C0 907 511 B) is always white, while when they are VALEO, they are black.

The motor (which, incidentally, is only clipped in, with no screws or solder joints) spins freely - when removed and connected to a 9V battery - and seems to be quite powerful.

Reconnected: The control lever (back to 9V) works perfectly and powerfully, and also returns to its original position when reversed. (Next, the potentiometer should be tested.)

Connect to pins 5+6. Pin 4 is not connected, and pins 1, 2, and 3 are for the potentiometer. The numbering is embossed inside the connector housing.

Phaidros wrote:

The engine (...) is, incidentally (...), running strongly. (...) Next, the potentiometer should be tested.

Yep, that aligns with the typical error pattern.
1) You can clearly hear the valves clicking, which indicates a functioning engine.
2) In VCDS, one can observe that the position values change abruptly and to varying degrees.

Both indicate a functioning engine but a faulty potentiometer.

Is the potentiometer actually hermetically sealed, or can dust simply accumulate on the sliding contact?

As far as I understand, potentiometers often have a small "blind spot" (for example, due to a speck of dust). Consequently, the desired value is not reached, but rather the system is constantly regulated around that value. This, in turn, causes the abrasive belt to gradually grind its way through the material next to the dust particle...

I would be interested to see some detailed photos of the potentiometer and a measurement you've taken, if you're willing to do that.

Greetings.
Guste.