Abs woes....again

[crazy88]

I've got another abs light on my car

Last year I lost all comms with the abs module via vcds so had it repaired and all was peachy.

I've now got an abs light (yellow abs light and red warning icon on dis)

A vcds scan tells me its "ABS valves supply voltage" code 01200.

Ive googled it, it suggests a low voltage (so I'll make sure my battery is nicely charged, but it's only a year or 2 old). However, it went flat a few months back when the kids left the interior light on all night. I charged it, but it only really does short journeys so perhaps it's just on the limit? I need to get a multimeter on it tomorrow.

Also possible faulty fuses. From what I've seen (and it's mostly passat forums where I've found info) they have a fuse box under the bonnet, right by the battery. The a4 doesn't have that does it? Does it just have the one under the steering wheel, where all the relays are. I had a quick look under the bonnet and couldn't see any fuse boxes.

If the only ones are those fuses and relays under the drivers knees, are any of those fuses for the abs? The fault light is on, but very occasionally goes off. So a slightly dicky fuse could be the cause? I've tried pulling all the control fuses in the side panel on the drivers side, and they're all fine. It's the beefy 50amp ones I'm on about. I can't find a wiring diagram for them.

Finally, I'm guessing it may be a faulty abs controller, again. If so, it has a 2 year warranty so I'll send it to get fixed, but it's a ball ache with the mot due in about a week.

So, does anybody have any other advice? Come across this problem before at all?

Any help would be greatly appreciated as always!

Cheers

 

[desertstorm]

http://wiki.ross-tech.com/wiki/index.php/01200
Have you checked the connector are correctly mated on the ABS module.

 

[crazy88]

Yeah, that's another thing I saw on the vcds page, so I'll be trying that too. Will make sure all the pins are clean too, I've read that a bit of corrosion could also be the cause.

Cheers

 

[Oranoco]

Whip the plug out and give both plug an socket a going over with electrical contact cleaner

 

[aragorn]

Its probably the usual fault resurfacing tbh.

The ABS fuse is up the back of the dash behind the central electrics bar with all the relays in it. Really big 50A fuse.

 

[crazy88]

I'll give the 50a fuse a look too.

I suspect it is the module, but just want to try eliminate everything else to make sure.

I'll be on this tomorrow as weather is forecast to be nicer so I'll report back with any findings.

Thanks again

 

[crazy88]

Checked the 50a fuse, it's fine. Charged the battery and still getting the fault.

I've whipped the top connector off and the contacts all look really nice and clean. Now to take the wheel off so I can access the second connector underneath which is apparently for abs pump power, so I'm hoping it's that!

If it's not that I'm lost and can only assume it's the controller again. Will take it out today while the wheel is off etc and get it sent off for test I guess?!

 

[crazy88]

Well, no luck with any of the above methods. I've still got my abs fault.

Cleaned the contacts, but all looked perfectly fine anyway. Checked the 50A fuse under the dash, and that was fine. Checked it with a multimeter also, and it registered 0 Ohms, so no reason to think it's bad (it visually looked perfect too). Connected and re-connected both ABS controller connectors multiple times, and cleared any faults to check it wasn't an existing fault still flagging it up.

I've ended up taking the module out as I said previously so that I can ship it off for retest all being well. If it's not that i'm really stumped.

From what i've been googling the ABS and air bag share the same power supply, if I have read it right, so if it was a genuine low voltage/ dodgy loom etc i'd be expecting air bag problems? (which i'm not getting).

Maybe one day I'll fix this and help somebody else out!

 

[superkarl]

 

[slepy]

Well, no luck with any of the above methods. I've still got my abs fault.

Cleaned the contacts, but all looked perfectly fine anyway. Checked the 50A fuse under the dash, and that was fine. Checked it with a multimeter also, and it registered 0 Ohms, so no reason to think it's bad (it visually looked perfect too). Connected and re-connected both ABS controller connectors multiple times, and cleared any faults to check it wasn't an existing fault still flagging it up.

I've ended up taking the module out as I said previously so that I can ship it off for retest all being well. If it's not that i'm really stumped.

From what i've been googling the ABS and air bag share the same power supply, if I have read it right, so if it was a genuine low voltage/ dodgy loom etc i'd be expecting air bag problems? (which i'm not getting).

Maybe one day I'll fix this and help somebody else out!

I have completely removed the airbag system/wiring from my car and no problems with abs. So doubt it is your issue there.

 

[crazy88]

I have completely removed the airbag system/wiring from my car and no problems with abs. So doubt it is your issue there.

Apparently the airbag is linked somehow on some vag cars, but as you say with yours removed it wouldn't have been that anyway.

I spoke to the remanufacture company yesterday and apparently my abs controller is completely dead, they couldn't even fix it, so they're sending me a new one off the shelf (most likely another refurb). It should be arriving today, so I need to fit and then sort out recoding it, which I need to google to find out how. I have VCDS though, so it should be OK.

I'll be re-fitting this new one, along with new brakes all round, over the weekend and will update how I get on.

 

[aragorn]

Dont think theres any coding needed on the non-ESP units.

 

[crazy88]

Excellent news!

 

[mojocvh]

Sorry to jump in on this thread but is there any way to check that you already have the correct part number module fitted to your car before sendng it away for rework OR is there anyway to cross check vehicle spec to part number?AJL engined 2000 1.8t sport quattro with edl...

thanks

Mo....

 

[aragorn]

AJL car should have a unit ending in A or E. Likely A if its original.

What is yours?

 

[mojocvh]

Hi mate, its # IS 8EO614111A

Having difficulty sourcing part number replacement ho .... hum, nearest I can find online is without the final letter??

bit of a minefield and trying to source info is difficult...

 

[aragorn]

Final letter must be 111A or 111E.

They are pretty rare. Theres a few on ebay, they're all over the £100 mark though.

it starts 8E0 not 8EO, which will help your search!

Your not V833 MOD are you?

 

[mojocvh]

No hmm good point that never thought about the bay..

 

[mojocvh]

Thanks for your help aragorn, I have located a repair agent who deals with the public [grr] and will get unit off today and sent off to them.

As the unit is away being tested/repaired I would like to carry out some simple tests at the multi pin connector out to the sensors prior to refitting it.

So does anyone have a link to either a image or wiring diagram of the ABS control module multipin plug that would allow me to bell out the lines to the sensors to eliminate any shorts or open circuits? BTW the failure mode of module is a no communication so we cant interrogate it...

cheers

Mo.

 

[aragorn]

I'd just plug it in and let the module do the checking once its fixed

 

[S4_dan]

So does anyone have a link to either a image or wiring diagram of the ABS control module multipin plug that would allow me to bell out the lines to the sensors to eliminate any shorts or open circuits?
Mo.

Like Aragorn says, you could wait until the module is connected and try scanning again.

BUT, if you really want to manually check the pin outs, I 'MIGHT' be able to get some diagrams off my Autodata. I won't be able to look until this evening or tomorrow morning though due to build a fence today.

Dan

 

[mojocvh]

Thanks that would be much appreciated Mo

 

[mojocvh]

Update.

Sorted!

ecutesting were able to confirm module was faulty, repaired it and returned over 6 days incl a weekend!

Unashamed PUNT for them as "the other" company only deal with "trade".......roll on another 110,000!

Mo.

 

[S4_dan]

Sorry I didn't get around to getting the diagram to you. It's been a mental few weeks with no sight of it easing in up any time soon.

Glad you have it finally sorted.