S4 - ABS/ESP light on

[^adam^]

Hi guys,

S4 B6 2004 Avant

This is an issue that I've been looking into for a while, if I can't fix it, I'll have to get Volks Autos to take a look when the car goes in for MOT next month but I'd rather get it sorted before.

VCDS showing code 00287, ABS Wheel Speed Sensor Rear Right (G44) Open to short

The speed sensor has been replaced twice, once with a genuine Audi part and one for Bosch part.

I've recently changed the car battery as the old one was only running at 65% capacity. I've also changed the brake light switch as had that code up.

The ASP/ESP lights only come on intermittently. Sometimes from start up, sometimes during a journey.

Any tips on the next steps?

 

[Darran]

Open circuit means either a bad signal due to electrical connections or maybe **** between sensor and ring or incorrect gap, worst scenario faulty abs unit.

 

[^adam^]

Since I wrote this, a quick trip in the car and on start up, the handbrake light flashes three times and the DIS said 'brakes' in red and beeped three times.

I'll go out and run another scan today.

 

[Darran]

Use the MVB in abs controller with vcds to see what each sensor is doing.

 

[Deleted member 85022]

Got this on mine at the moment. Although it's the front left.

It was a faulty abs sensor and the ecu was damaged and had to be repaired by an ecu doctor.

The esp and abs lights would come on and go off throughout a journey until one day they just never went off...

 

[^adam^]

Haven't had a chance to re-scan yet, will do again tomorrow evening.

Obviously, one end of the loom is where the ABS sensor connects, but I have no idea where it goes after that.

Darran - good tip on the VCDS, I'll get the misses to drive whilst I look at the laptop.

 

[ARtechnik]

Have a look at your measuring blocks if the rear right sensor fluctuates like from 20-40-30-50mph then most likely will be your wheel bearing as the sensor picks up the signal from there if it doesn't give you a reading at all then most likely it will be a wiring issue or the abs pump

 

[^adam^]

Quick re-scan now showing both rear sensors.

00287 - ABS Wheel Speed Sensor; Rear Right (G44)
27-00 - Implausible Signal
00290 - ABS Wheel Speed Sensor; Rear Left (G46)
30-00 - Open or Short to Plus

So the rear right has changed error and the rear left now showing. I have a working Audi part that I took off the rear right that I can swap the rear left to, are the rear sensors the same?

A quick look at the measuring blocks showed the rear right showing the correct speed and the rear left showing nothing.

I'm starting to lean towards the module, as the rear right has been changed for a new part and is showing the correct speed on the measuring blocks (great tool!).

The brake buzzer is also coming on the car on start up now. Only starting happening recently. The brake pedal travel has also increased significantly, not sure if that's related?

 

[ARtechnik]

You need to check the wiring before going for the abs module

 

[frankc]

Increased pedal travel and a start-up warning? Have you checked the fluid level??

 

[^adam^]

Not good news today from Volks Autos unfortunately. Needs new ABS module at £1050 fitted

Need to call them back with what to do but no idea as yet.

 

[Darran]

Put a secondhand one on and code it up!

 

[^adam^]

Just spoke to them again, apparently it's the whole unit, including pump.

Explains the extended pedal travel to reach a bite point.

A quick look at a couple of online parts manual suggests the part number is 8E0614517R

 

[AudiLeon]

Where are you based? Someone may be able to help you fit it.

 

[^adam^]

South Croydon.

Getting the car back this evening. Quote from Mike on here suggests the part is £1500 new for the full unit so guessing VA were replacing just the electrical part, not the mechanical part. I will double check this with them later.

I'll report back, just for people using the search in future more than anything!