Strange experience yesterday.,,,

 

Took car for the MOT, passed with no issues.

 

Key in, drove down the road abs & traction & power steering light on...

 

Drove back the garage, the brake fluid cap was not on, asked if they removed it to check the level as the bigger boost pipe does restrict the view, answer  = No we havent touched it  - First concern these are not trusted.

 

found the cap on the shelf under the reservoir, i put back on said will drive it home and clear the codes, as i didnt really want them touching it with snap on crap diagnostic.

 

Codes clear, they do not instantly come back, but after another scan are back. The dash lights do not remove.

 

Took car back, had the wheel off checking left abs sensor as i took my laptop to show the code on vcds. 

 

Now the Wires have been broken in the past, and soldered back and on inspection seem a good job and should not be failing, so that really only leaves the sensor.I use the car everyday, its my commuter. Not as if ive not used it for 6 months and pulled it out of storage for the MOT.

 

So:

Would the MOT test the rotation of the wheels more then daily use?

How did it pass, as these faults would fail it :P

Not to sure what to do going forward with this garage.. On one hand ive picked my car up in a worst condition than when i dropped it off, on the other hand the wires where damaged and repaired before hand.

Not to forget the dodgy drama of the brake fluid cap, that they didnt touch :P

This Garage passed the car the year before, without issue - Why i used them.

No reason to touch the fluid cap on an MOT so they shouldn't have interfered with it.

What is the ABS fault code?

No reason to touch the fluid cap on an MOT so they shouldn't have interfered with it.

What is the ABS fault code?

Ye i know, but they have. But why?

 

I forgot the save the fault, It was open / closed  G47 front left

Need a bit more info on the code if you want help really.

The garage cannot 'make' an ABS sensor fail unless they pulled and damaged the wiring, suggest you simply repair/replace the dodgy wiring/sensor, clear codes and carry on.

 

You're not going to get anywhere with the garage, they've passed it and had their £30 or whatever tiny amount of money they make for an MOT, in case you hadn't realised the only qualification for a service manager at a garage is to be a an immovable liar, you could have video evidence of a technician removing the brake fluid cap and they'll still flat out deny it to your face.

I can't see why an ABS-related fault would bring on the power steering light?

I can't see why an ABS-related fault would bring on the power steering light?

Ye it does, and there are no fault codes showing for power steering, and steering feels fine. Not heavy or anything.

 

I will scan after, first to check fuse 25, then to check abs control unit connections. Then wheel off and multi meter check on the end socket. Anyone know what volt it should be?

If you are meaning what voltage there will be at the connector with the ABS sensor disconnected - I'd have to ask "why"?  That sensor is effectively used as a pulse frequency generator, if anything, put a scope across the O/P of that sensor and spin the wheel, you should see a pulse being generated on a working sensor.  If you have VCDS, why not have a look at the signal from all four wheels, I think that you can do that with VCDS, saves poking a DMM across some wires?

If you are meaning what voltage there will be at the connector with the ABS sensor disconnected - I'd have to ask "why"?  That sensor is effectively used as a pulse frequency generator, if anything, put a scope across the O/P of that sensor and spin the wheel, you should see a pulse being generated on a working sensor.  If you have VCDS, why not have a look at the signal from all four wheels, I think that you can do that with VCDS, saves poking a DMM across some wires?

Not on the sensor side, i want to test the wires to the sensor. 

Ye it does...

 

I had the main 40A ABS pump fuse out of ours this morning to test something, and that resulted in the ABS light and the (red) brake system warning light next to it being on, but not the power steering light, so it's not something that 'just happens' when you have an ABS fault, as far as I can see.

Edited 27 August, 20169 yr by Wino

all connections to the abs controler seem fine, think pin 12 and 28 are the sensor, so i guess just test power at the end of the wire. If thats good its the sensor, would you say?

If you are meaning what voltage there will be at the connector with the ABS sensor disconnected - I'd have to ask "why"?  That sensor is effectively used as a pulse frequency generator, if anything, put a scope across the O/P of that sensor and spin the wheel, you should see a pulse being generated on a working sensor.  If you have VCDS, why not have a look at the signal from all four wheels, I think that you can do that with VCDS, saves poking a DMM across some wires?

show how to test the sensor 

Need a bit more info on the code if you want help really.

VCDS-Lite Version: Release 1.2

Saturday, 27 August 2016, 15:38:01:0

Control Module Part Number: 6Q0 907 379 H

  Component and/or Version: ABS/ASR 5.7 FRONT   V30

           Software Coding: 00188

            Work Shop Code: WSC 13765

                      VCID: 42F7C90B5D97

1 Fault Found:

00283 -  ABS Wheel Speed Sensor; Front Left (G47)

        30-00 -  Open or Short to Plus

 

VCDS-Lite Version: Release 1.2

Saturday, 27 August 2016, 15:38:31:0

Control Module Part Number: 038 906 019 LA

  Component and/or Version: 1,9l R4 EDC 0000SG  4904

           Software Coding: 00102

            Work Shop Code: WSC 13765

                      VCID: 61B52687F851

1 Fault Found:

18061 -  Please check DTC Memory of ABS Controller

        P1653 - 35-10 -   - - Intermittent

So open short circuit to B+ is a broken wire.

So open short circuit to B+ is a broken wire.

yes and ive checked it all, the repairs are good all soldered together no frays, no looseness... think im going to have to get a new loom :(. No room left to chop again.

 

just in case im a moron, it is left hand side from the drivers perspective? and not facing the car lol?

Edited 27 August, 20169 yr by FromTheDarkness

You have checked it from the ECU to the sensor? What resistance value did you get?

You have checked it from the ECU to the sensor? What resistance value did you get?

I read it should be between 15 -16 and it was 15.80 

 

ECU to sensor? you mean abs controller to sensor?

yes and ive checked it all, the repairs are good all soldered together no frays, no looseness... think im going to have to get a new loom :(. No room left to chop again.

 

just in case im a moron, it is left hand side from the drivers perspective? and not facing the car lol?

 

Left is left when sitting in the car and facing forward.

Maybe an alarmist posting and not relevant in your case, but I've only, so far had one ABS problem with a car, it was a VX Cav GSI 4X4 and it was still under used car warranty, so handed it in to main dealer, they replaced FNS sensor - wrong, still faulty, they replaced FOS sensor - wrong, still faulty, while waiting to take it back in, I scoped all four sensors and got an output from all of them, then I "looked back" into the controller with a high impedance DMM and found that one channel was a lot different impedance wise than the other three, so told dealer when I handed it back in, they replaced the RNS and ROS sensors - wrong, still faulty, I told them it was still faulty and again what I had found ie faulty controller, they took it back in and replaced the FNS and FOS sensors, still faulty, at last they ordered in a new controller - booked me in and replaced the controller, 5 minutes later I drove away with no faults!  Please note, each time the workshop supervisor had taken my car out for a short test drive, - with me, each time the fault only took about 5 minutes or 1/4 miles to show up!!!!! The workshop always claimed that I did not know what I was doing and they had equipment to talk and test that car's ABS system, it was only a few years later that I discovered that the next generation of Bosch ABS controllers were catered for by the VX main dealer diagnostic tools, that version was not.

Edited 27 August, 20169 yr by rum4mo

Left is left when sitting in the car and facing forward.

 

Im on the correct side then :P

Maybe an alarmist posting and not relevant in your case, but I've only, so far had one ABS problem with a car, it was a VX Cav GSI 4X4 and it was still under used car warranty, so handed it in to main dealer, they replaced FNS sensor - wrong, still faulty, they replaced FOS sensor - wrong, still faulty, while waiting to take it back in, I scoped all four sensors and got an output from all of them, then I "looked back" into the controller with a high impedance DMM and found that one channel was a lot different impedance wise than the other three, so told dealer when I handed it back in, they replaced the RNS and ROS sensors - wrong, still faulty, I told them it was still faulty and again what I had found ie faulty controller, they took it back in and replaced the FNS and FOS sensors, still faulty, at last they ordered in a new controller - booked me in and replaced the controller, 5 minutes later I drove away with no faults!  Please note, each time the workshop supervisor had taken my car out for a short test drive, - with me, each time the fault only took about 5 minutes or 1/4 miles to show up!!!!! The workshop always claimed that I did not know what I was doing and they had equipment to talk and test that car's ABS system, it was only a few years later that I discovered that the next generation of Bosch ABS controllers were catered for by the VX main dealer diagnostic tools, that version was not.

 

Well vcds is pointing to a broken circuit, and with there already been a repair job on the wires... no matter how good they look must be the issue, im guessing it has some corrosion that i cant see. I will replace the sensor as its cheap, but not looking forward to the replacement of the abs wire, not really sure where the top end goes.

Any idea what gauge wire is used? Im not paying £57 for three wires!!

 

I will buy the wire and re wire it all 

Anyone have any ideas to the above? The two wires going to the sensor.

I'd go for something like this:

 

http://www.ebay.co.uk/itm/RUBBER-2-CORE-6-AMP-0-75-ROUND-BLACK-MAINS-ELECTRICAL-CABLE-FLEX-BY-THE-METER-/321564057344

 

Should be flexible, yet robust and outdoor-capable, and cheap.

I'd go for something like this:

 

http://www.ebay.co.uk/itm/RUBBER-2-CORE-6-AMP-0-75-ROUND-BLACK-MAINS-ELECTRICAL-CABLE-FLEX-BY-THE-METER-/321564057344

 

Should be flexible, yet robust and outdoor-capable, and cheap.

cheers thanks for that