ABS/traction control seems to have stopped working have engine warning light traction control abs and flashing handbrake light with beeping. Have replaced the abs unit but has not sorted the issue. don't seem to have any communication with the abs module using the vagcom. Have checked the fuse links on the battery and the fuse in the box next to the steering wheel. Also checked the power and seems to be getting the volts and the earth to the plug for the abs module. Any more suggestions would be much appreciated. 

 

Your wiring to the alternator has broken under the gearbox where there is a connector, to say this problem is common would be an understatement, it's an easy fix though.

Have fixed that issue but the abs still no luck.

Maybe keep fixing it until the 17911 code stops appearing? Have you tried clearing it?

Yes just left with the 18061 and 18057

In that case I'd be carefully examining the pins of the ABS module connector (both module ones and loom connector ones), then if everything there looks clean and dry, head back up the loom looking for damaged wires, Looks like CAN wiring might be favourites for being involved, and they are generally a twisted pair which may make them easier to trace.

Getting the correct voltage on the 2 power and the 2 ground seem ok also. There is 60 ohms resistance between the twisted pair. 

What year is the car? It looks like a 1.9, rather than the 1.4 in your profile?

 

Try resistance checks from each of the twisted pair pins to chassis, ideally after it has rained (artificially if necessary!)

Edited 20 October, 20196 yr by Wino

Indeed it is a 1.9 vrs. And what should the resistance be and should it change ignition on and ignition off? 

I think I'd expect each to be isolated (very high resistance) from chassis (but never tried this personally). A lower resistance might indicate a fault where wiring had rubbed on metal edges and was causing an intermittent short circuit, possibly only when wet.  All a bit hypothetical, but the leg of wiring that comes down out of the scuttle area tends to be a bit of a river in rainy conditions, and there are areas where the loom is close to metalwork down in that area.

Do you have access to ABS module?

Yes I have 2 modules as thought it was that and bought one from a breakers fitted it but did not resolve the issue. 

Are there any relays or fuses apart from the ones on top of the battery and one in the fuse panel side of the dash? 

No.

 

As stated this is almost certainly a CAN wiring fault, you need to trace it from the ABS module back.

A quick glance at wiring diagrams suggests there are more 12V feeds than you've mentioned.

Pins 1, 7 and 25 should have permanent lives, and pin 35 should have an ignition switched one.

Actually, that might all depend on when the car was built, the above info was for May 2004 onwards (not sure if it changed again later too).

Before this there were only 3 feeds, on different pins.

Pleeeease tell me when your car was made.

It is a 54 plate vehicle.

21 minutes ago, AndySpeare567 said:

It is a 54 plate vehicle.

 

So's mine, but it was made in 2001, the VIN number would clinch it.

Ah ok I will get the vin number tomorrow. 

4 hours ago, AndySpeare567 said:

Yes I have 2 modules as thought it was that and bought one from a breakers fitted it but did not resolve the issue. 

I mean diagnostic access

I have vcds but that's no use as it won't communicate. 

6 hours ago, AndySpeare567 said:

I have vcds but that's no use as it won't communicate. 

Yhat’s what I mean. Sounds like you have checked lives and earths though so that leaves the data bus wiring. On the ABS that’s normally where the wiring loom curves around under the ABS unit on the n/s chassis leg. Water collects there and rots the loom out. 

9 hours ago, AndySpeare567 said:

It is a 54 plate vehicle.

 

So probably the four feeds as mentioned above, but if it was made earlier, it'll just have 3, two permanent 12V feeds on pins 2 and 6, and an ignition switched one on pin 23.

Is there somewhere I can get the wiring diagram?