Warning Light ABS? Brakes? Unsure
audifan
A2OC Donor
Can you list the exact sizes of all 4 tyres fitted to the car. One wrong / mismatched tyre can throw up errors. although unless you have had a new tyre this fault should have been there before now.
We really need that VCDS scan results to narrow down this issue.
How good is the battery / alternator as low voltages do cause electrical warnings - noticed the date on your clock is 2000.
We really need that VCDS scan results to narrow down this issue.
How good is the battery / alternator as low voltages do cause electrical warnings - noticed the date on your clock is 2000.
PlasticMac
Member
There have been many valid ideas as to the cause of the abs warning and brake alarm indications on the dash put forward so far.
All of them would trigger an error, which in turn would be seen on a VAG specific scan.
@safbeafbe said a scan was done, and showed no logged errors.
If that scan used a scan tool compatible with the A2, the fault is, most likely, not sensor related.
If the scan tool was A2 incompatible, then, as @audifan has said, before doing anything else get a VCDS or OBD Eleven scan done, and we'll all have a very good idea of the cause.
Mac.
All of them would trigger an error, which in turn would be seen on a VAG specific scan.
@safbeafbe said a scan was done, and showed no logged errors.
If that scan used a scan tool compatible with the A2, the fault is, most likely, not sensor related.
If the scan tool was A2 incompatible, then, as @audifan has said, before doing anything else get a VCDS or OBD Eleven scan done, and we'll all have a very good idea of the cause.
Mac.
datsundrew
A2OC Donor
That’s exactly what I thought, but absolutely no codes stored. I have VCDS.
PlasticMac
Member
So, I'd suspect the dash cluster, or connections to it.
Mac.
PlasticMac
Member
Also, check ECU connector.
Mac.
datsundrew
A2OC Donor
I know where the ecu connector is, how wou I check the dash cluster? I changed out the Yaw sensor today, and the same as usual, 5 miles or so and it does the same.
i did another scan, and got this….DTC memory??
This comes up every time I scan, is this a clue?
Im assuming that I scan in ‘ABS’ and don’t need to look elsewhere?
Attachments
PlasticMac
Member
Check this from Rosstech http://wiki.ross-tech.com/wiki/inde...If power is missing or,addition to a no-start.
Sounds like an ECU or ECU connector problem, that is preventing the ECU from dealing with errors as it should.
I'd start with the ECU connector, and the loom into the engine compartment, on the engine side of the bulkhead.
I'll have a look at the electrical schematic on the morning, see if I can give any clue.
Mac.
Sounds like an ECU or ECU connector problem, that is preventing the ECU from dealing with errors as it should.
I'd start with the ECU connector, and the loom into the engine compartment, on the engine side of the bulkhead.
I'll have a look at the electrical schematic on the morning, see if I can give any clue.
Mac.
datsundrew
A2OC Donor
Great, thanks for that, its much appreciated! This is absolutely doing my head in now. The main issue is the Mot is due in November, and I can’t see how I’m going to get this sorted. There’s no way it’ll not beep and flash it’s lights in the 45 mins on the ramp. I’d happily to get it fixed, but with this blithe issue it is it really wants someone who knows their stuff. I’ve researched this to death now, and seem to be going around in circles. You suggesting ecu loom, plugs etc does put me on another path to the usual brake switch, abs sensors, bearings, yaw sensor etc. I’ve replaced so much on it, imagine if this was a garage randomly throwing bits at it!
Brendanfelix
Member
Would it not do this if the handbrake wasn't properly off, or the switch was faulty, so the car doesn't know the handbrake is off?
datsundrew
A2OC Donor
Possibly? But the hand brake light goes out on the dash when off, and on with it up, so I can’t see it’s that simple. I may try it with my other A2 to see.
Brendanfelix
Member
If the handbrake light does go on off with the handbrake going up and down, then it's almost certainly not that then. I don't believe there's a 2nd switch/sensor just to tell the engine management that the handbrake is on or off. It's a fair assumption that the one switch does both jobs, but I stand to be corrected by those who know more.
PlasticMac
Member
I think that the fact that the dash shows errors, that are not stored in the ECU, or are not being reported via the OBD port, points to an ECU related fault. Until the ECU is fully functioning, we don't know if there are other, maybe ABS related faults on the car.
Because the car runs, and there is no physical manifestations of problems, I am guessing, (that word again), that the ECU itself is OK.
I'd remove the ECU, check for damage, and dampness, and then check the plugs and sockets for cleanliness and security when latched.
Clean with a contact cleaner, (not WD40), and allow to dry before reassembling. WD40 do a branded contact cleaner which is good.
Mac.
Because the car runs, and there is no physical manifestations of problems, I am guessing, (that word again), that the ECU itself is OK.
I'd remove the ECU, check for damage, and dampness, and then check the plugs and sockets for cleanliness and security when latched.
Clean with a contact cleaner, (not WD40), and allow to dry before reassembling. WD40 do a branded contact cleaner which is good.
Mac.
steve_c
Grumpy OAP & A2OC Donor
Here are several suggestions for professional help.
VASS of Bath have an excellent reputation, and are familiar with the A2. They're reasonably local to you:
Home | Vass of Bath Ltd
www.vassofbath.co.uk
Gary at B&F Autos in Hounslow is an acknowledged A2 expert. A pretty straightforward trip down the M4:
B&F Autos Ltd
Car Mechanics, Car Servicing, MOT's, All Makes and Models. VW & Audi Specialists.
www.bfautos.co.uk
Slightly further away, WOM Automotive near Stoke, who certainly know their way round an A2!:
All three of those suggestions are independent VAG specialists who charge fair prices. I'd suggest you look for someone to get this sorted sooner rather than later, so you're not under pressure because of the MOT
Shippers84
Member
I have had the same issue, do you get brake lights when all the warning lights are lit on the dash? With warnings illuminated I had no brake lights, a scan reported an issue with the brake light switch but came back as ‘intermittent’ or ‘indeterminable’ signal (I’ll try and find the scan report and be more specific). I had, for no better word of it, a bit of a fiddle and shove around under the dash above the pedals and the issue has gone away, unless I have to stomp on the stop pedal and it comes back, but usually resets once the car is switched off and on. I would suggest changing the switch as a first port of call, mine I suspect is on the way out and gets jammed if excessive force is used but is fine in normal day to day use. It’s on the to do list before the winter sets in!
datsundrew
A2OC Donor
Thanks, I’ve had the ECU out today and had a good look, things look ok and no signs of damp or damage and the plugs seem ok and locate into place ok. I used some contact cleaner I had which I had to use on our old Volvo 850 window switches every few months. I also took out the headligh to clean the earth there.
still no change, I did a scan on both the ABS and engine and it reports the same.
datsundrew
A2OC Donor
Good call! I’ve not checked that, I am however on my 3rd switch in less than a year! no1 went, no2 was a black one which was rubbish, and now the green one which seems ok. Since the green switch I’ve not had and faults logged. I will go for a drive tomorrow to try this out.
Shippers84
Member
Mine must have been done before, the lower dash trim in that location is not what I’d describe as factory fitted
Where did you order the green switch from? I’ve seen them on eBay, just want to make sure I get the best I can as I’ve read it’s not a particularly enjoyable job to do.
datsundrew
A2OC Donor
Yes eBay. The green switch seems so much better quality than the black ones.Mine must have been done before, the lower dash trim in that location is not what I’d describe as factory fitted
Where did you order the green switch from? I’ve seen them on eBay, just want to make sure I get the best I can as I’ve read it’s not a particularly enjoyable job to do.
datsundrew
A2OC Donor
I’ve just been reading about abs pump and control repairs, companies such as ECUrepairs are all saying the eps/ traction/ abs lights are classic symptoms of it failing, and also then failing to communicate with the ecu. I’m wondering if it’s worth a shot sending it off for testing and repair? apparently they keep the coding so when it’s returned it’s plug and play.