ABS Module

[RoboticCherry-Coke]

Hey guys,

The abs light started coming on in my calais the other day. When I start the car the light doesn't come on until I start moving forward. I have checked all the fuses and disconnected the battery for a while but it still isn't working.

What could be causing this? Am I going to have to replace the ABS module? If so, how difficult is it do this?

Cheers

[Brett_jjj]

It is more likely to be one of the wheel sensors than the module.Im not sure how much they cost to replace.There is a way to test the ABS system in a similar way to doing an ECU error test that flashes the engine light.But this test flashes the ABS light.Im not sure how this is done,my VS does not have ABS fitted.But Ive read about it on here before.Maybe try a search for something like ABS error code checking or similar.Or someone else might know how and post how to do it it here for you.

[Brett_jjj]

I just found out how to do it,its very similar the the ECU error checking. You just connect pin 5 and pin 12 in the ALDL connector then turn the ignition to the ON position..This will make the ABS light flash any logged error codes .I will see if I can find what the actual codes are.

[Brett_jjj]

12 Diagnostic system operational
21 Right hand front wheel speed sensor fault
23 Right hand front wheel speed sensor continuity fault
25 Left hand front wheel speed sensor fault
27 Left hand front wheel speed sensor continuity fault
28 Wheel speed sensor frequency error
31 Right hand rear wheel speed sensor fault
33 Right hand rear wheel speed sensor continuity fault
35 Left hand rear wheel speed sensor fault
37 Left hand rear wheel speed sensor continuity fault
41 Right hand front inlet solenoid valve circuit fault
42 Right hand front outlet solenoid valve circuit fault
45 Left hand front inlet solenoid valve circuit fault
46 Left hand front outlet solenoid valve circuit fault
55 Rear inlet solenoid valve circuit fault
56 Rear outlet solenoid valve circuit fault
61 Pump motor relay circuit fault
63 Valve relay circuit fault
71 ABS control module internal fault

Heres a list of the error codes.If you are not sure about doing this test just let me know and I will explain to you how its done.It is really easy to do though.

[RoboticCherry-Coke]

You are a legend! I will go give it a shot now and see what happens. I will let ya know the results.

[RoboticCherry-Coke]

OK all tested... I get a 12 then a pause then I get a 25.

So that tells me that there is a fault left hand speed sensor. I have recently replaced the front brakes could something I have done caused this?

Is this something I can fix/replace myself? Where abouts is it located?

Any help with this would be great. Cheers.

[Brett_jjj]

All you can do is check the wiring and connectors.Make sure they are clean and tight.If no difference then you will need a new sensor.At least you know what it is now. Too easy.Remember you will have to clear the logged error first before going for a drive,then run the test again on the the ABS to see if the error is gone or has come back..Disconnecting the battery for a couple of minutes should do it.

[Dangerous Dave]

there is a plug on he back of the hub with i think an 8mm bolt holding it in, make sure that it wasnt damaged or dislodged when you did the brakes.
unfortunately, if the sensor is stuffed,you need to replace the hub as it is a sealed assembly. not cheap, but definately worth going genuine..

i went through 3 sets of non genuine when i did mine, all for ABS but all had faulty/wrong sensors, and 2 sets had that much movement, they were unroadworthy..

[RoboticCherry-Coke]

Ok cool I had a quick look just before and the bolt seemed fine but I will take a closer look during the day. I had a quick look on ebay and a second hand hub is only $50. Any ideas how much a new genuine one is?

[hako]

I'd go with what Dangerous Dave says above, plus also check the cable that goes to the plug from the chassis is not cut or damaged - when pulling the caliper you may have accidentally bashed it. On mine the cables are starting to crack from age.

[RoboticCherry-Coke]

Yeah, when I had a quick look I didn't jack the car up or anything just stuck my head under there and everything looked tight but it was only a quick look. I followed the cable up into the engine bay and it was plugged in nice and tight there. I will just have to wait till its daylight before I can take another look, hopefully it just as simple as a loose cable.

[RoboticCherry-Coke]

Just finished playing under my car and its all fixed. Got under there and disconnected the cable, all looked good but I spread the pins a bit further a part to make sure they had a secure connection with the plug. Put it all back together, disconnected the battery and BAM! it started working again So thanks heaps for all your help guys.

Oh and if anyway is interested I went into my local holden dealer to find out prices of a new hub. From memory it was $450 for a genuine one and $275 for an aftermarket one.