no dash display. Ignition switch?

Try a proper vagcom lead rather than a generic odb2 tester.

Perhaps theres some interference from the alternator or something?
 
yeah as Aragorn says you can interrogate the comfort electronics and instruments with a vag based tester but a generic obd one will only show sensor failures. Theres an instrument cluster diagnostic in vag com too as far as I remember. Just got mine this morning so not had time to play with it yet but I will tonight :)

The autec vag405 scanner is cheap, works well and is vag specific - can be had off ebay for £40 etc - i've got one and it is good for quick diagnostics but vag com kicks **** for everything once you learn how to fly it.
 
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Thanks muchly. :)

I'll have a look through those and hopefully find out where the issue lies.
Although the problem seems to be getting worse.
I guess the battery isn't at it's best now due to all the testing and trial starting.
So charged it up but still a bit weaker than I'd like.
But now the dash doesn't light up at all until you try to start it.
It no longer starts either, it was low on fuel so I put another gallon in and still it only starts for a second then cuts out.
I'm not sure if the fuel pump is priming.

My OBD2 diag kit will read and clear the ABS/Airbag/AT codes but gives a 'link error' on the engine menu.
Wasted a lot of time on it this week when I'm supposed to be prepping my reliable track car for Cadwell on Monday, so may just ignore it until after that.
 
Been away so not had chance to properly look through those diagrams yet.

But went to it today to see what it was doign today.
And the odd thing is that it is trying to start again but the immobiliser light is flashing , so it starts then immediately stops again.
So seems the fuel pump is priming and when it does run for those few seconds the dash works normally.
Wierd!

So could a dodgy dash be causing all these problems?
And would a dash repair/refurb/replace fix it perhaps?


I've had the immob issue before but then it went away until now.
I don't actually have an immob on the car in that the key has no internals so I assume no immob actually fitted.
But it does have the remains of a Clifford alarm that I found the other day, obviously not connected to work though.

Any ideas welcomed.
 
I think the dash module is faulty itself mate. It does contain the immo (well part of it and part is in the ecu) but this is a failure mentioned by BBA Reman the ecu and dash specialists as a known problem, I would try a set of instruments from another car if you can but should get it scanned for fault codes using Vag Com or VCDS as it will be way better than obd. By the way, to get access to abs, airbag and A/T but get a link error on the engine module, is a bad sign. The engine module should be the first and last module to respond to any tester but the others can be flaky depending on the tester or car year of manufacture as full obd compliance is post 96. Could be a faulty ecu, blown obd "K" line (after market stereo fitted?) or a blown fuse in the ecu compartment (black box in the scuttle panel at the drivers side) or a bad ecu relay (109?)
 
evilscotsman said:
Could be a faulty ecu, blown obd "K" line (after market stereo fitted?)
Click to expand...
Yes it does have an aftermarket stereo.
I'll look up this 'k' line.


Any suggestions on best place to get VAG com?
Does it come as software and cable to use with pc or laptop?
 
Interestingly, the ECU doesnt connect directly to the diag plug.

The engine ECU's K line goes to the cluster, and then the clusters k-line goes to the diag socket.

When you query the ECU you can usually hear the cluster clicking as the transfers the signal to the ECU.

The ECU's K line also carries the immo data to and from the clocks, so the issues are all likely to be related.

Have you checked the plugs in the back of the clocks are plugged in correctly?

The key will have an immo transponder in it. Its a small glass phial, perhaps 1cm long embossed into the insides of the key.
 
Yep, had the clocks out and checked the plugs a couple of times.
Made no difference.

aragorn said:
The key will have an immo transponder in it. Its a small glass phial, perhaps 1cm long embossed into the insides of the key.
Click to expand...
Ah, will that be the little thing in a slot on the one part of the keyfob? (just pulled the fob apart to have a look)
 
measure with a volt meter between pins 4 and 7 on the obd socket, should be 9v, higher than that may indicate the stereo fault, and none means no connection from the cluster to the obd socket or a short circuit at the cluster. strange you can read the abs etc tho...

maybe an addressing fault in the ecu itself as all modules use a 2 wire comms link so they have a unique address that is fired over the bus when the scan tool queries one of them, and only the engine "module" isnt responding.....
 
Tested the OBD socket and it gives 9.5v on pins 4 & 7

If you looked at the car right now you'd think the (only) problem was the immobiliser.
The light flashes and it starts and immediately cuts out as it does when the immobiliser is still doing its thing.

Think I might investigate that next.
Although it seems I'm just chasing various possible problems around right now.
 
The immo is part of the cluster, so given the clusters crazyness, and now an immo failure, it does all point at the cluster having given up the ghost...

The Engine ECU does not sit directly on the diag line. The engines diag line also carries the immobiliser data, and so originates from the cluster. When you request access to the engine ECU over the diag bus, the cluster forwards the data onto the ECU, so again a cluster fault will stop the ECU from responding to vagcom etc.
 
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OK now the immobiliser light doesn't flash until you try to start it.
This is the same even with the wiring unplugged from the imob reader on the ign barrel.
 
I'm thinking that way Aragorn, even though it 'appears' that the cluster is now working OK again (as far as the display/gauges are concerned).

Problem now being to justify the amount of money already spent on this supposedly reliable daily driver whilst my track car gets totally neglected and used while this thing is off the road.. was meant to be the other way around.
Talk about pointless money pit !

If I could be sure the cluster would cure it I'd have no choiuce but to get it done. To spend more money and it not be that would have me reaching for the fuel & matches.. probably for myself as I doubt it'd even burn properly.

Any suggestions on cluster solutions?

Cheers.
 
No idea, don't have Vagcom.
My OBD2 VA specific tester gets a linking error on the engine module.
 
Well given you have a cluster fault, you really need to see whats going on with the cluster...

Spend the £10 and buy a vagcom cable on ebay.

In the mean time, you can connect a link wire between the car diag pin on the cluster plug, and the ECU diag pin on the cluster plug and get to the ECU that way if you want, i doubt its going to tell you much though.
 
audi upgrades
aragorn said:
Spend the £10 and buy a vagcom cable on ebay.
Click to expand...

Any ones to avoid?
I read somewhere that some are only partially functional and you need to buy a reg key.... is this so do you know?

Well I've ordered one now anyway.
Will see how it goes when it gets here.
At least it gives me a good excuse to stay away from it for a couple of days.
 
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Ye, the cheap ebay leads only give you the freeware access unless you buy a licence, but thats enough to access the modules and read fault codes etc.
 
the b5 link cable should be kkl type, but im sure the can and hex-can ones are backward kkl compatible, just make sure it does kkl anyway whatever happens.
 
Got the Vagcom and plugged it in.

Reads a lot of thingsand has thrown up a few codes and cleared most.
Immobiliser pick-up ring is one it found but laptop died before I could clear that one.


But it's getting errors on the engine modules same as the other reader.
Basically saying it cannot communicate with the controller.
 
as i've said above, bypass the cluster and see if the diag to the ECU works.

I dont have the wiring diagram to hand, but there will be a pin on the ECU labelled as "W-Diag" and a pin on the cluster labelled as "K-Diag" or just "K". Unplug the cluster, connect the W and K pins together and try to access the ECU again.
 
Will do that tomorrow probably.. getting dark now.
I assume that is without the cluster plugged in then... or connected to the pin with cluster plugged in?
Is the ECU pin I need accessed at the ECU itself? (so under the bonnet) or is that on the cluster plugs as well?

Have two faults showing up on the 'instruments' menu.
01128 immobiliser pick-up coil (D2)
01176 not giving me fault but seems it's faulty key or the like.

Also getting an ABS code
01203 electrical connection between ABS and instrument cluster open or short to ground

All faults can be cleared but re-occur immediately.
 
they are hard wiring, connection or power faults then mate. you obviously have a bad cluster or a wiring / power fault to the cluster so its getting in the way of other modules and giving codes that all point to immo and cluster.....I think the next thing is a cheap cluster from the breakers or pull it and check for power where it should be and grounds where they should be, on the multiplug that goes into the rear of the cluster. also check the ecu plug itself for corrosion, as moist air goes upward into the compartment from the drivers footwell and cant escape so its always got white crusting on the alloy casing of the ecu, electrical contact cleaner is worth a try on the ecu and cluster plugs and sockets, also check for blown fuses inside the ecu compartment, there are a few critical ones in there.
 
OK I bypassed the cluster and have accessed the engine module.

got 5 fault codes from it.

18010 - power supply terminal 30: voltage too low
P1602 - 35-10 - - - Intermittent

17978 - P1570 - 35-00 control module locked

18020 - P1612 - 35-10 - Intermittent Electronic Control Module Incorrect Coding

17967 - Throttle body (J338): fault in basic settings
P1559 - 35-10 - - - Intermittent

17973 - P1565 - 35-10 - Intermittent Idle Speed Control Throttle Position lower limit not attained

Will look up those codes to see what they actually are.
Added the other fault descriptions.


So does the cluster bypass indicate a cluster problem is likely over anything else?
 
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locked engine module is immobiliser message (immo on and triggered), terminal 30 is the main battery feed to the ecu so bad connection or blown fuse there, coding fault - weird, may be a side effect of the battery voltage to the engine module, TB codes could be a pointer to what circuit is down too.

Check a wiring diagram to see what fuses or circuits or relays are common to the tps and ecm then you may find it.
 
The battery low voltage is probably from when the battery was almost flat.

I've cleared the codes so will plug the cluster back in and see what it throws up now.
 
So I've plugged the cluster back in and....



Yes, it runs.
Bit sluggish on idle but suspect it needs resetting after all this nonsense.
Going to check for codes etc shortly.
And sort out the lack of brake lights.

Other than that you'd never know there'd been a problem.
 
Damn laptop died before I could do anything.

But the light problem is affecting brake lights (not third) & dipped beam headlights.

Wish my Elsawin would install properly as I think it has wiring daigrams....
 
ok, the brake light switch is powered off the same fuse (S102 25A in ecu compartment) as the maf, N75 and N18, so if that had gone you would get codes for them (hard unclearable codes) - maybe a wire has pulled off the brake pedal switch when you been taking the console out? (your feet may have strayed?) hang on will look up the wiring diagram on mine (is yours diesel?)
 
Source for the brake lights will be completely independent of the ECU. Electronic throttle cars have two switches on the brake pedal, one for the lights, and one for the ECU, so presumably the ECU switch is fed from the ECU power supply.

My guess is a bad earth/power feed somewhere around central electrics.

Given its affecting the cluster and the brake lights and headlights...

I wonder if it could be something like the X contact relay? Big beefy relay that supplies power to a lot of the "ignition live" stuff? There should be a pin marked 75x in the central electrics panel that you could test for voltage.
 
So the lights problem was a new one, which took me to things that may have occured since the first problem.
And it was the relay wasn't pushed all the way in, possibly from whem I was checking them all through the hole in the side panel.

The car starts fine and everything is back to how it was before.
Apart from a slightly rough idle after warm-up, could be down to low fuel perhaps.
Can't set the TB and stuff as my VCDS isn't registered yet.

Might even take it out for a drive shortly.
Keeping fingers crossed that it'll start at the fuel stop!
 
Took it out and put some fuel in it.
Then gave it a quick hose down. It started and stopped then.. but only the once. May have been damp from the wash.

It starts OK and runs mostly OK but occasionally it seems to be missing on 1 or 2 cylinders. Only at low revs.

Showing no codes at all now.
 
So the missing has goen away and all is fine....


OK so it's not really all fine. :sadlike:

After a short period of having the ignition on, engine running or not.
The 'coolant' warning flashes up.
The dash tells me to 'switch off engine and check coolant level'
Coolant level is topped up but this makes no difference to the warning.
Vagcom gives no codes.

Any ideas folks?
 
coolant level sensor wire off? and you may have a dodgy coilpack or 2 causing the misfire. most other things would cause a code of some sort.
 
Just checked the sensor wiring, looked perfect, so shook the tank about a bit and plugged it back in.
No more warning light. So possibly a crapped up/sticky sensor.
Although I'm taking nothing for granted with this car.
 
aye im learning that too ha ha....meanwhile the tinfoil subaru plows on...
 
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