D3WZ: Diagnosis and Troubleshooting Guide

Hello!

Is it possible to connect the D3WZ to the onboard diagnostics system (there is a free pin)? If so, what would be the consequences? This is a question that has been on my mind for a long time.

Best regards, Peter.

As far as I know, there's a special diagnostic device for this that you plug between the power cord and the auxiliary heater. It then displays any error codes that are stored.
I can't imagine that you'll be able to connect the auxiliary heater to the K-line so easily.

"Does the main heater rely on the diagnostic system? Am I completely wrong about that? There's a separate menu option for the auxiliary heater in VAG COM, isn't there? It seems the electronics of the heater aren't designed for the K-line. That's a shame. I know about the adapter cable, but I just wanted to know if anyone has tried using the K-line before."

Thank you and best regards, Peter.

The auxiliary heater is connected to the K-line (address word 1.
Try it out and see if it works for you; I'd be interested to know the results.
You can't really break anything except for a fuse.

Not only the auxiliary heater, but also the supplementary heater models D4WZ/D5WZ are connected to the K-line. I would also be interested to know if it works with the D3W model.

Hello!

Is it possible to connect the D3WZ to the onboard diagnostics system (there is a free pin)? If so, what would be the consequences? This is a question that has been on my mind for a long time.

Best regards, Peter

D3WZ - no, because only the so-called 'free running diagnosis' is integrated.

B/D4W or B/D5W - yes, because it has integrated VAG diagnostics.
Unfortunately, this is not the case for every related control unit. Please provide the part number (which is printed on the control unit and requires it to be removed) so I can inquire further.

Ich hab auch eine D5WSC, welche manchmal anspringt und manchmal nicht. Funny.
I also have a VAG-Com. So, I could simply try connecting the K-line from the SH unit to the vehicle's onboard network and then see if I can access it via VAG-Com? Can VAG-Com distinguish between Webasto and Eberspächer systems?
Is there anyone who has managed to do this and can share their experience?

'I have a Thermo Top C here, and I can't even read it using the Webasto diagnostic tool.'
However, it uses a VAG-COM interface (two different types), which is supposedly supposed to work...

I can read out my Eberspächer heater via the TP5 .

CU Gremlin.

@Gremlin
Can you access the auxiliary heater using VAG-Com? Did you simply connect the K-line of the auxiliary heater to the vehicle's onboard network (also a K-line)?
Can a standard troubleshooting process be applied there?

Do you have any instructions on how to use the TP5? I also have that remote control.

@Gremlin
Can you access the auxiliary heater using VAG-Com? Did you simply connect the K-line of the auxiliary heater to the vehicle's onboard network (also a K-line)?
Can a standard troubleshooting process be applied there?


Please read my post again .


Do you have any instructions on how to use the TP5? I also have that remote control.

Turn on Facebook.
Press the 'P' button twice to enter time setting mode (the time will flash).
Press and hold the 'P' button for 2 seconds -> Display shows 'oooo'.
Press the 'Heating' button.
Press the 'P' key.
Press the 'Heizen' button twice.
Press the 'P' key.
FB reads error -> Display shows 'F0xx' -> F0 to F5 = error number (0 = current error; 1-5 = stored errors); xx = error code.
Use the arrow keys to navigate.

Clear error: While the error message is displayed, press button P -> The display will show 'dEL'.
Press and hold the 'Heizen' (heating) button for 2 seconds.


Service manuals are awesome!

CU Gremlin.

Thank you, Gremlin.

I will try that out.
Based on everything I've read here, I now have a pretty good idea of where the source of the problem lies.
I have a TDI with 110 horsepower (not the PD type), and in that case, you're supposed to tap into the diesel line near the front of the engine compartment using a T-connector.
'I've also experienced that. I mean, I've seen air bubbles occasionally in the fuel line leading to the starter heater (SH), and those bubbles then migrate into the SH, likely preventing it from working properly or even igniting. When the engine is running, the SH starts without any problems. This is probably because there's pressure in the diesel line when the engine is running, which also reaches the SH, thereby reducing or eliminating the air bubbles.'

Regarding the error codes again, I unfortunately can't find any in my manual. Could you please help me with that? Is there a table or any reference materials available?

Thank you very much!

I assume that your vehicle (110 hp) has a VP37 injection pump, which means it doesn't have a pre-injection pump, and therefore there is no pressure in the diesel lines.
It is possible that the air bubbles are being "sucked away" by the engine.

I have the TDI 110 hp engine (not the PD type), and in that case, you should tap into the diesel line with a T-piece located at the front of the engine compartment.

When using a charging station (SH) with an external booster pump, the electricity is always drawn directly from the main power supply.

Everything else just causes problems (the pump is completely empty, the resistance through the filter is too high, etc., etc., etc.).

CU Gremlin.

Thank you for the tips.

I just followed the installation instructions, and they say NOT to take anything out of the tank. If I still want to do that, how should I proceed? I certainly can't just drill a hole in the tank...
Are there any helpful tips or instructions with pictures?
And please again, does anyone know the error codes?
'By the way, the pairing process with my TP5 didn't work. After the time starts blinking and I press the P button for 2 seconds, nothing happens; it doesn't display '0000', but the time continues to blink. Could it be because I didn't connect the K-line wire in the SH connector as described in the manual? The instructions say to 'disconnect' it. I did disconnect it.'

I just followed the installation instructions, and they say NOT to take anything out of the tank. If I still want to do that, how should I proceed? I can't just drill a hole in the tank...

There are special nozzles for that.

Are there any helpful tips or instructions with pictures?

Sure, here are the installation instructions.

And please again, does anyone know the error codes?

google, or http://www.espar.com/htm/tecmans.htm

The pairing with my TP5 didn't work, actually. After the time starts blinking and I press the P button for 2 seconds, nothing happens; it doesn't display '0000,' but the time continues to blink. Could it be because I didn't connect the K-line wire in the SH connector, as stated in the instructions? It says you should 'disconnect' it. I did disconnect it.

'Good question. What *exact* type of heating system do you have? Is the TP5 unit customized in any way? Everything runs normally on the TP5 until the error reading process begins (i.e., when you press the 'P' button for the last time). Only when it attempts to read the error memory would a disconnected hose become relevant.'


CU Gremlin.

Thank you, Gremlin.
I have a D5WSC and everything is wired according to the plan. What does 'custom' mean in this context?
I'm a beginner and I'm hoping to find tips for beginners in this forum as well.