ABS light on but no error code.

[Thekayyceeful]

So either way ill be stuck having to deal with paying for software to be done... does the programing have to be done to put a new pcm in have to be done at holden or can that be done at any mechanic that change it.

 

[BlackVXGTS]

You need to find someone that has a Tech2 scan tool or equivalent (same tool used by Holden to perform diagnostics). Not all OBD-2 scan tools will diagnose the ABS.

Just to clear up previous posts, VX Commodores have a number of computers (or modules) that communicate with each other:
. ECU (generic name for an Electronic Control Unit) - types are ECM (Electronic Control Module for manual cars), and PCM (Powertrain Control Module for automatic cars)
. BCM (Body Control Module)
. ABS (Anti-Lock Braking System Module), sometimes associated with the ETC (Electronic Traction Control Module)
. ECC (Electronic Climate Control Module)
. SDM (Sensing and Diagnostic Module for the Airbag or Supplementary Restraint System)
. Dashboard module (can't remember the actual name)

That's why, when you have a problem, unless the cause is obvious, you really need to have your car scanned for errors to avoid unnecessary (and expensive) replacement of parts that may not fix the problem. The various modules above retain any errors that have been logged, but many scan tools only display engine or PCM codes. Unfortunately, in the real world not all problems are logged, especially intermittent problems, so scanning for errors does not always identify a problem area. Below is the most common ABS problem that involves multiple instrument panel lights:

"Instrument warning lamps (ABS) - The ABS module consists of 2 main parts. A hydraulic unit and an electrical unit. The most common failure seen with the module is when the ABS Electronic module fails. This often results in a myriad of dash lights being illuminated, not just the ABS light. When the ABS Electronic module fails, it can also interrupt scanning procedures for the ABS, BCM (Body Control Module) and PCM (Powertrain Control Module). Another cause can be water entry into the engine harness connection area, under the bonnet, against the right strut tower. Apparently, water gets onto and through the "horse-shoe" shaped plastic wiring support, which eventually tracks down to the ABS connector, causing all sorts of warning lamp issues. Foam fillers and sealants are used to help reduce the amount of water that can get through to these areas."

In the VS Commodore you could replace the electric module (unit), without impacting the hydraulic module (unit). From my reading of the Holden VT/VX service manual, it seems that you have to remove the complete ABS unit, including all the brake fluid lines to replace the electric unit, and then re-bleed all the brake lines, which is a more involved process.

The other advantage of using a Tech2 (or equivalent) scan tool is that it will identify the specific part number of the modules installed in your car. For example, if you are convinced that the ABS unit is your problem, the scan tool will tell you the specific part number installed so that you can purchase a replacement on eBay or anywhere else.

 

[Thekayyceeful]

^^^ thankyou so much so much info

 

[Husky]

I have a Tech2 too in Pakenham, happy to scan your car properly if you ever come this way.

 

[mpower]

You need to find someone that has a Tech2 scan tool or equivalent (same tool used by Holden to perform diagnostics). Not all OBD-2 scan tools will diagnose the ABS.

Just to clear up previous posts, VX Commodores have a number of computers (or modules) that communicate with each other:
. ECU (generic name for an Electronic Control Unit) - types are ECM (Electronic Control Module for manual cars), and PCM (Powertrain Control Module for automatic cars)
. BCM (Body Control Module)
. ABS (Anti-Lock Braking System Module), sometimes associated with the ETC (Electronic Traction Control Module)
. ECC (Electronic Climate Control Module)
. SDM (Sensing and Diagnostic Module for the Airbag or Supplementary Restraint System)
. Dashboard module (can't remember the actual name)

That's why, when you have a problem, unless the cause is obvious, you really need to have your car scanned for errors to avoid unnecessary (and expensive) replacement of parts that may not fix the problem. The various modules above retain any errors that have been logged, but many scan tools only display engine or PCM codes. Unfortunately, in the real world not all problems are logged, especially intermittent problems, so scanning for errors does not always identify a problem area. Below is the most common ABS problem that involves multiple instrument panel lights:

"Instrument warning lamps (ABS) - The ABS module consists of 2 main parts. A hydraulic unit and an electrical unit. The most common failure seen with the module is when the ABS Electronic module fails. This often results in a myriad of dash lights being illuminated, not just the ABS light. When the ABS Electronic module fails, it can also interrupt scanning procedures for the ABS, BCM (Body Control Module) and PCM (Powertrain Control Module). Another cause can be water entry into the engine harness connection area, under the bonnet, against the right strut tower. Apparently, water gets onto and through the "horse-shoe" shaped plastic wiring support, which eventually tracks down to the ABS connector, causing all sorts of warning lamp issues. Foam fillers and sealants are used to help reduce the amount of water that can get through to these areas."

In the VS Commodore you could replace the electric module (unit), without impacting the hydraulic module (unit). From my reading of the Holden VT/VX service manual, it seems that you have to remove the complete ABS unit, including all the brake fluid lines to replace the electric unit, and then re-bleed all the brake lines, which is a more involved process.

tons of great info - however you can absolutely replace just the electronic part on a VX. I'd correct that if I was you it is completely wrong. I must admit I am very lucky. I have two cars with the same module so I just played swapsies to confirm my suspicions, not everyone has that luxury - including workshops with scantools.

Scanning is all well and good unless the entire system goes haywire with a faulty ABS module.

 

[BlackVXGTS]

tons of great info - however you can absolutely replace just the electronic part on a VX. I'd correct that if I was you it is completely wrong.

You may well be correct, but these are the instructions from the Holden VT/VX Service CD:

3.6 CONTROL MODULE
NOTE:
Remove the new control module from it’s protective package only when it is ready to be fitted to the hydraulic modulator.
REMOVE
1. Disconnect battery earth lead.
2. Remove hydraulic modulator and control module assembly, refer to 3.5 HYDRAULIC MODULATOR AND CONTROL MODULE ASSEMBLY in this Section.
NOTE 1:
The hydraulic modulator and control module assembly must be removed due to the specified installation position of the control module (the spring plate(s) will not seat correctly unless it is in a horizontal position).

 

[Thekayyceeful]

I have a Tech2 too in Pakenham, happy to scan your car properly if you ever come this way.

I would take you up on your offer, but I'm too sure about driving my car without rego all that way (even with a permit) bit of a catch 22 need to get this fixed to get it regoed but need rego to get down to you find out what to fix.
But I'm sure that I'll find someone with a Tech2.

 

[Thekayyceeful]

Okay okay okay, great news i got my new tailshaft put in by a friend and while he was waiting for me to pick up the car he scanned and cleared all my codes. The airbag light is now off. But the abs light is still on BUT the good news is it came up with a code!
So Im atleast one step closer to getting it fixed atleast.
Just really exited and wanted to tell someone.

 

[mpower]

You may well be correct, but these are the instructions from the Holden VT/VX Service CD:

3.6 CONTROL MODULE
NOTE:
Remove the new control module from it’s protective package only when it is ready to be fitted to the hydraulic modulator.
REMOVE
1. Disconnect battery earth lead.
2. Remove hydraulic modulator and control module assembly, refer to 3.5 HYDRAULIC MODULATOR AND CONTROL MODULE ASSEMBLY in this Section.
NOTE 1:
The hydraulic modulator and control module assembly must be removed due to the specified installation position of the control module (the spring plate(s) will not seat correctly unless it is in a horizontal position).

I assume the "hydraulic modulator" is generally part of what is sold as the electronic module (not sure what that is referring to).

These things are easy to replace with minimal fuss.

 

[BlackVXGTS]

............But the abs light is still on BUT the good news is it came up with a code!

What was the code.