Faulty instrument cluster
 

I have had the following codes along with an EPC and check engine light on the dash since October, 2011.

18084 - EPC Warning Lamp (K132) Circuit: Electrical Malfunction
P1676 - 35-00 - -
18098 - Malfunction Indication Light (K83): Electrical Malfunction
P1690 - 35-00 - -

As I need to get my car smogged, and California requires vehicles to not only pass the emissions test, but a dash indicator light functional test (lights must come on with ignition on/ engine off, and then turn off once car is started), I needed to get this fixed, but had run out of ideas.

I previously checked or did the following:

1. Throttle body alignment (several times) with VAG-Com
2. All engine wire harness plugs, hoses, air box clips and connections.
3. Removed APR ECU, replaced with stock ECU, cleared codes, ran car and re-scanned. Dash lights and codes returned. Put APR ECU back in.
4. Removed instrument cluster to check bulbs. Discovered that 'bulbs' are surface mount LEDs. Re-installed cluster.
5. Cleaned battery connections. Load tested battery = good. 13 volts at rest, 10.5 volts under load held for 15 seconds, 14.5 volts while running (alternator).

I finally took the car to an Audi mechanic where it has been for 2 weeks. He scanned it and found the same codes, but with no faults associated with them. The car runs and drives fine and passes emissions tests. He believes it is a faulty instrument cluster. Audi wants over $1200 for the cluster, plus it needs to be programmed. Total parts and labor for that = about $2000, plus all of the diagnostic time already in it. According to my mechanic, you can not just install a used cluster from another 2.7t as the security features will not syncronize and used ones can not be coded to another car - ??

I suggested rewiring the LEDs for EPC and check engine to other known functioning cluster lights that come on and turn off properly, but he said that each light controls other functions that would cause real issues with emissions or other functions if disconnected, or connected through another path.

At this point I am prepared to scrap the car before putting $2k more into it - all because of 2 little LEDs that are not turning off.

Any final ideas from anyone?

Thanks

Pull the cluster and send it out to be repaired. Google for audi instrument cluster repair. Should take less than two weeks. Take the car home and do it.

BTW, SOME audis can be driven w/o the instrument cluster...of course you will have no speedometer or other instruments, but you can wing it if you're careful and drive with traffic.

Codes do indicate a cluster problem, and re-wiring it is a bad idea.

You certainly can switch the instrument clusters, it's just not trivial. The immobilizer is part of the cluster, and it must be programmed to the keys you have. To do that, you will need the PIN code for the new cluster. Dealers can not get it for you - VAG set things up so that the dealer hooks up their diagnostic equipment to your car, and it communicates directly with the factory through the Internet - they never even see the PIN. A good automotive locksmith can retrieve the PIN, but only after the cluster is installed in the car. With the PIN, you can program the immobilizer to your keys with a VAG-COM. You will also need to transfer other settings (mileage, Km/Mi, etc.) Make sure the new cluster is as exact a match as you can find for the one you have now - same year, model, continent, etc. as close as possible.

Check these out:
http://www.audizine.com/forum/showth...ibility-issues
http://wiki.ross-tech.com/wiki/index.php/Immobilizer

You might also want to check with the people who repair these clusters (like BBA in the above video) to see if they can repair your problem.

Jim

First choice is repair, not 'also check with...'

Thanks for the replies.

All of the cluster repair options I have found were for the display fading out, not issues such as what I am having. I asked one of them several months ago if they could fix this issue, and they said they only repair the displays, but this was one I found on Ebay. I will contact the other repair places to find out if they can fix this kind of thing. According to my mechanic, this is a long shot.

I'll let you know what I find.

Well, there are several on e-bay right now, depending on your year etc. Probably worth $100 to try. You might check with RossTech, but I'm pretty sure you can change between manual and auto trans with a VAG-COM if necessary...
Jim

I talked to 2 more "repair" places, and none of them have the equipment to diagnose or repair issues with the clusters such as what I'm experiencing. The equipment they have does not simulate the cluster being in a car = lights on with key and off once engine started. Their equipment just turns on the cluster to check lights, gauges and display. All of my lights are functional, so they will not have a way to check where the fault is that is causing the EPC and CEL to stay on.

I found a couple of clusters from a place called LKQ for around $120, but no way of knowing if they have the immobilizer function. Mine in my car HAS the immobilizer. My understanding is that an immobilizer cluster can not be easily if at all reprogrammed for any other car other than what it originally came in. Does anyone know more about this?

It is a crap shoot if I buy one, as there is no return policy, and a limited exchange policy.

The best option would be to borrow a cluster from someone with an A6 to see if it would work, or if the lights turn off if it did, and then go from there, but these cars seem to be thinning out around here.

I suppose it is worth $120 to find out, but if it doesn't work one or two times, I'm either going to have to scrap the car or sell it out of state to somewhere that does not have the same unreasonable smog testing requirements as California.

I did get a quote back today from Southern Electronics in Richmond VA for $335 (parts, labor, shipping) and they claim that they can not only repair it, but that there will be no charge if they can not repair it. I'm not sure how they verify that it is fixed, and I am not sure what is the best way to go.

I don't know if I have a better chance of success with a used one or repair of mine. Repair costs double, but if they really guarantee it, that might be the way to go.

Plus, if they repair it, there's nothing to re-code or set up, just plug it back in. That's what I'd try...
Jim

I also live in CA, so I have to deal with the same things. If the car passes emissions requirements, who cares if it has a dash light illuminated?

As an alternative, if you keep running into a wall with this, you may try to find a "friendlier" smog check place. There are plenty around, and you can usually get a recommendation from one of the local car forums.