Trailer Control Module Not Responding

Hello everyone,

I installed a trailer hitch on my Golf 5 and registered the control unit in the installation list.
All functions are working, including the automatic deactivation of the fog light on the vehicle when a trailer is attached.

However, communication with the control unit is not possible, as can also be seen in the scan results.

It is equipped with the Westfalia e-unit 321 800 300 113.

The e-module was included in the complete package for the VW Golf V hatchback (1K1) (10/2003 - 02/2009).

Is the software incompatible with the diagnostic interface?

Thank you in advance.

Werner.

Is this an original VW control unit or from a third-party supplier?

If you're relying on third-party providers, it's no wonder things aren't working.

Hi,
If you look closely, you will see that the error message appears in the "Comfort System" module of the control unit, and it occurs sporadically.
The diagnostic interface, engine, control panel module, and braking electronics appear to be working correctly. Therefore, the statement "no communication possible" is not entirely accurate.
I would delete the error message and observe whether and when it reappears. Possibly, there is a missing entry in the coding or adaptation of the comfort system.
What does the manufacturer say?
Was ist die Herkunft dieser Westfalia suspension kit? Where does the information come from that this suspension kit was originally installed on the Golf 5?
hg
Herbert.

Subsystem 1 - Component: Sounder, not mounted.
Subsystem 2 - Component: NGS, not mounted.
Subsystem 3 - Component: IRUE n.mounted


"Something seems to be incorrectly coded here. Is this the original comfort control unit? Why is an alarm system configured when it's obvious that the siren, tilt sensor, and interior monitoring system are not installed?"

First of all, thank you for the answers.

The tow hitch was new; according to the description, it was an AHK (German tow hitch brand) specifically designed for the VW Golf 5 (produced from 2003 onwards) and compatible with the vehicle's existing electrical system (eSatz) from Westfalia.
The company is therefore new.

The manufacturer's hotline informed me that, due to the defect, the part number is 321 600 300 113 from Westfalia. It likely contains a component from Hella, but has a different wiring harness.

Herbert wrote:

Hi, If you look closely, you will see that the error message appears in the "Comfort System" module of the control unit, and it occurs sporadically. The diagnostic interface, engine, control panel module, and braking electronics appear to be working correctly. Therefore, the statement "no communication possible" is not entirely accurate. I would delete the error message and observe whether and when it reappears. It's possible that there's a missing entry in the coding or adaptation of the comfort system. What does the manufacturer say? Was ist die Herkunft dieser Westfalia suspension kit? Where does the information come from that this suspension kit was originally installed on the Golf 5? hg Herbert

I had already cleared the error memory. However, I hadn't yet activated the trailer stabilization system, and now it seems the error is gone.

Ich habe es noch nicht überprüft, aber ich denke schon, dass das Stg. mit seiner Adresse auf den CAN Bus sendet, dass ein Anhänger dranhängt und somit das entsprechende Stg. (Ich nehme mal an, das Bordnetzsteuergerät, habe noch nicht im Schaltplan geschaut) die Nebelschlussleuchte am Fahrzeug abschaltet. Jetzt habe ich noch den Blinker getestet mit ausgebauter Blinkerbirne,auch das wird durch die erhöhte Blinkfrequenz und in der MFA angezeigt und im Fehlerspeicher vom Bordnetzsteuergerät abgelegt. SI don't understand. Please provide more context or clarify your request.

I'm assuming that the issue is simply a diagnostic incompatibility.

Diagnostic communication is a completely different matter, operating on a higher layer within the CAN bus, and I believe that's where the problem lies.

vag-driver wrote:

Subsystem 1 - Component: Sounder, not mounted. Subsystem 2 - Component: NGS, not mounted. Subsystem 3 - Component: IRUE n.mounted Here is something incorrectly coded. Is this comfort control unit original? Why is an alarm system configured here, even though it is obvious that a siren, tilt sensor, and interior monitoring system are not installed?

I've only had the car for a short time, and everything is original. Since there are no known issues regarding the alarm system, I haven't looked into it further yet.

Nachdem ich es jetzt mal überprüft habe, sieht es für mich schon richtig aus. Die 3 Komponenten sind über die lange Codierung deaktiviert. DenNo, that's correct as is.

Thank you for the information.

Hi there.

Quote:

I had already cleared the error memory.

But I hadn't yet activated the trailer stabilization, and now the error seems to be gone. }
Does it work now?
What problem remains now that you're mentioning incompatibility?
hg
Herbert.

vag-driver wrote:

Why is an alarm system configured here, even though it is obvious that the siren, tilt sensor, and interior monitoring system are not installed?

Speculation mode:
1) Originally, the DWA-Low model did not have an IRÜ (integrated roof unit) or NGS (navigation guidance system), but it did have a siren.
Then the siren is either waterlogged or the battery is dead (a common issue with its age). The previous owner then chose the simplest way to avoid error messages and had the siren deactivated.
"Originally, the vehicle didn't have a horn, but the previous owner wanted it to be activated. Now, when the door is opened, at least the turn signals flash. He may also have connected a simple horn to the relay output of the control unit. This is a solution common in North America and can be coded. However, I haven't verified the coding for this."
3) Are you sure that the LIN subsystems will also be queried, even if no DWA (Drive-by-Wire) coding is present? (I don't know how I would verify the coding without a connected vehicle).

Herbert wrote:

Hi, Quote: I had already cleared the error memory. But I hadn't yet activated the trailer stabilization, and now the error seems to be gone.

Does it work now?
What problem remains now that you're mentioning incompatibility?
hg
Herbert}

Hello Herbert,

The self-diagnosis is missing. As can be seen in the scan, VCDS is querying address 69, but the control unit is not responding.

What works is the communication on the CAN bus. Here, each control unit "shouts" its information onto the CAN bus using its CAN address, and the control units that need this information receive it. For example, the body control module reports "turn signal lamp on" (by changing a bit in the data bytes of the body control module from 0 to 1), and the trailer control module receives this information and turns on the turn signal lamp on the trailer.

However, querying a control unit with VCDS requires more than just basic CAN bus communication. Now, the desired query needs to be transmitted within the data bits, for example, "show me the error memory."
In this communication, information is exchanged through the data bits, and the same protocol must be used. When you query a control unit with VCDS that is not recognized, you see "Trying xxxx" at the top of the display, and VCDS then tries different "languages" to communicate with the control unit. Only when everything fails does VCDS indicate that the control unit is not responding.

And the control unit installed in my device probably can't support any of those options.
I'm going to talk to the supplier now to see if I can get the other e-invoice.
"However, I don't want to have to pull the cable harness out of the connectors and fuse box again and replace it with another one. Instead, I would like to rewire the contacts in the connectors on the trailer control unit accordingly. The same wires are needed (terminal 30, terminal 15, terminal 58, CAN High, and CAN Low)."

guste100 wrote:

Why is an alarm system configured here, even though it is obvious that the siren, tilt sensor, and interior monitoring system are not installed? vag-driver wrote: Speculation mode: 1) Originally, the DWA-Low model did not have an IRÜ (integrated roof unit) or NGS (navigation guidance system), but it did have a siren. Then the siren is either waterlogged or the battery is dead (a common issue with its age). The previous owner then chose the simplest way to avoid error messages and had the siren deactivated. "Originally, the vehicle didn't have a daytime running light (DRL) system installed, but the previous owner wanted it to be activated. Now, at least the turn signals flash when the vehicle is unlocked. It's possible he also connected a simple horn to the relay output of the control unit. This is a solution commonly used in North America and can be coded. However, I haven't verified the coding for this." 3) Are you sure that the LIN subsystems are also queried, even if no DWA (Drive-by-Wire Actuation) is coded? (I don't know how I would check the coding without a connected vehicle). Hello Guste, Is it similar with the Golf, like it is with the Polo? I know that a different comfort control unit is installed if the vehicle has an alarm system. But your speculation could certainly be correct; however, the PR codes only contained this information, which doesn't necessarily indicate a DWA.

4K3: Radio-controlled central locking system, operable from the inside and securely protected.



I believe it should work now, as the "DWA not active" flag is enabled in the coding. In VCDS, when viewing the comfort control unit settings, you can see the three modules listed with "not mounted."

The thread jumps back and forth between two topics, which doesn't make it very easy to follow.
Maybe we should split it up?
Regarding the initial topic again - the trailer control unit is obviously not a problem for the vehicle's internal network, but it is for VCDS.
Which interface are you using?
hg
Herbert.

Herbert wrote:

The thread jumps back and forth between two topics, which doesn't exactly make it easy to follow. Maybe we should split it up? Regarding the initial topic again - the trailer control unit is obviously not a problem for the vehicle's internal network, but it is for VCDS. Which interface are you using? hg Herbert

Do you mean the VCDS interface? It's a Hex-USB+CAN interface.

Well, I don't think it makes sense to separate the two issues. I don't have any error entries related to the DWA (trailer wiring adapter), and it's unlikely that's the cause of the trailer control unit not communicating.

Westfalia stated that I should use the other eS kit with the number 321 600 300 113. The kit installed is a universal eS kit for VW, but on the online portal where I ordered the complete package, it was listed as an eS kit specific to certain models. The problem that it is not diagnostic-compatible in the Golf 5 seems to be known there.

I'm not sure what I'm going to do yet. I'll get the wiring diagram for the original VW control unit, and then connecting it to the existing wiring harness isn't that difficult. It's probably the best and cheapest alternative.

I checked it again, and the communication error in the comfort control unit is back.
I recently purchased a used, original VW control unit with the part number 1K0907383. I also have the wiring diagram, and the connectors are included.

Hello everyone,

Today I connected the 1K0907383 control unit, and everything is working. It responds to requests with VCDS, and I have checked all the functions; everything is correct.

Regarding the issue with the configuration of the comfort control unit, I had the opportunity on Friday to read out another Golf 5, and in that vehicle as well, the three messages appear indicating that the components are not installed. See the picture.