9caregiver

Greetings all.

I have an odd thing happening on my 93 RSA. While driving ALL of the warning lights and sometimes the beeping alarm come on without notice. This can happen 1-4 times during a drive and sometimes not for a few trips. I have to turn the ignition switch off to reset the lights.

The car has only 9,000 original miles. I bought the car last year and have put on 2,000 of those miles. There are no modifications or repairs to the harness. The battery is new and the connections are clean. I do not use the car in the rain. This has been a problem since I own the car. I thought this might go away with some use. It has not. I feel the alternator may be spiking. Some have told me bad ignition wires? Has anyone had a simillar condition? Because of the untouched nature of this car I am reluctant to take too much apart without a direction. Thanks for any help.

Best,

Don

J-McDonald

My C2 did the same thing - it was creating an error code for a "hall sensor" fault, but it ended up being a corroded coil wire. A couple of other Rennlisters have had the same problem and it was bad coil wire, cracked spark plug boot(s), or bad distributor cap. It'll be very hard to diagnose visually - the first step should be bringing it to the dealer and having them hook up the Bosch hammer and see what error codes it has. Good luck - at least yours is doing it consistently, my car did it only intermittenly for the first month or so (of course, never when I tried to show the dealer).

Adrian

Dear Don,
Ignition switch problem. One of the contact banks might be loose. Slide in under the dash and take a look. If your regulator is shorting and spiking you will feel a physical surge or impending stall. I am assuming you are still running when the lights all come on. This is normally caused by a bad ignition switch. If it is just loose you do not stall. If it is badly worn you will lose power to the DME relay and you will stall
Ciao,
Adrian
964C4

PS: The only other thing I know of which is exclusive to the RSA is corrosion in the motherboard of the electrical distribution (central electric). The area around fuse No 2 is most venerable. If the distrbution ICs corrode and fail then it gets expensive. Corrosion is caused by time not by mileage.

Jim Howley

I also had this problem with my C2 and it turned out to be the ignition coils though for some reason there was something else wrong with it and the combination of the two problems made it very difficult to diagnose.

Off the top of my head I can't rememeber what the second problem was but I'll try and get hold of my mechanic and double check with him as to what it was.

Jim.

Fred, Long Island

Could be any of the above. Last year, mine started with identical symptoms. It deteriorated into a surging at idle and ultimate stall. We finally diagnosed the DME control unit as bad. I was advised that the fault originated with a shorted plug wire(s). Based on age alone, maybe a new set is in order. Good luck.

9caregiver

Thanks guys, I will start checking over the weekend for anything obvious. Adrian, The car does not surge or stall when the lights come on. Will let you know. Again thanks guys.

Best,

Don

91C2wrencher

Don, I had a similar, albeit not the same problem, my mechanic snooped around and found two very loose spark plugs. tightened them all was fine. $0.02 worth.....

Adrian

Dear Don,
The fact that you are just getting the lights, no surge, no splutter, no stall no other indications except the warn lights ALL on suggests the ignition switch. This happened to me twice. I left my solar charger in and all the lights came on in every instrument after about 5 mins. I thought Adrian you silly bugger. I stopped pulled the charger and 5 minutes later the same thing happened. After stuffing around I found the problem. The ignition switch was worn and my keyring was too heavy. When I knocked it the lights would come on. I have lightened my keyring dramatically and the problem will not occur unless I get nasty with the key ring.
The clue is nothing else happens.
Ciao,
Adrian
964C4

9caregiver

Adrian,

Thanks for your last reply. I will check the connections as I doubt with 9,000 miles and one key on the ring there would be much wear. I will let you know. Thanks again,

Best,

Don

bj

Hi Rennman

I had the exact same problem - turned out to be a bad coil wire and distributor caps. Before I discovered the problems the hammer indicated bad hall sensors. Previous owner disconnected the "!" switch to mask the problem. I discovered it by the sound of electrical clicks in the left hand side of the engine bay (ie. coils). With the engine idling and in the dark I could see the electrical arcs around the distributor's hi tension leads and with the covers removed from the coils. The hi voltage (EMI) spikes were causing havoc on the more sensitive low voltage electronics - such as the sensors. The cruise control would be working fine then all of a sudden the car would speed up and then correct itself - I suspect the hi voltage spikes were interfering with the speed sensor signal.

Hope this helps
Bill

Adrian

Dear Bill,
This disconnecting of the warn systems is becoming more common. I am helping a person now who purchased his C4 2 weeks ago only to discover after asking for help that somebody had a fault with this C4 and disconnected everything they could find to hide it. I guess luckily for the new owner they forgot something.
You problem is known as the christmas tree effect. This problem activates certain warn systems as you have correctly suggested but there are some it cannot activate and this is how during troubleshooting based on the owners input of course that the subtle differences can be identified.
Ciao,
Adrian
964C4

9caregiver

Greetings,
I checked the connection at the back of the ignition switch. It is clean and looks new. Last night I was able to use the car for a while. I wiggled the key while driving to try and set the lights off. That did not do it. Any other ideas to tell if it is the switch? Later on the lights came on 5 different times in a short span of time then for the rest of the trip all was fine. The car will be going in for a major service soon and I will have the caps and plugs replaced and the wires checked. Thanks all for your input.

Best,

Don

Adrian

Dear Don,
Try putting a little pressure on the key to turn it to the left. If it is not the switch and based on the fact that ALL the lights come on including the ones in fuel indicator (low fuel and low washer fluid) you will need to check the central electric. ALL lights on means you are in lighting test and this is controlled by an input from the ignition switch position, to the central electric and then to the central informer which is also under the dash. The only other item which can turn all the lights on is the central informer. This is found under the dash to the left of the ignition switch and headlight switch. It has two plugs into it. Maybe you should check thiese are secure. Maybe pull them out and reinsert them. I have heard of the rare failure of these units. Mainly related to issues when you turn the lights on and off though. However worth a try. We have to start with the most common and work towards the less common. If NOT ALL your warn lights are coming on at the same time then this is likely an ignition related problem in the engine or a harness problem. The key is the warn lights.
Ciao,
Adrian
964C4

9caregiver

Thanks Adrian,

The key will not move to the left and the switch feels tight as new. All of the lights do come on including the gas and wiper indicator. Last night the check engine light stayed on for a short while before going out. The beeping alarm also was sounding. As an aside sometimes I get a split second flash of the lights and they go out. Is the informer a tin covered box? Thanks again and I will keep trying.

Best,

Don

Adrian

Dear Don,
Yes it is. The split second flash of the lights I have heard of this once before combined with all the lights. It was a wiring problem behind the dash. The headlight power lead and the light high beam switch wiring on the column stalk along with some wiring to the central informer.
This might be a tough one to find.
I am assuming the lights flash without being selected on as well as when they are on. This points to wiring problems behind the dash if my assumption is correct.
I might advise you start with the column stalk switch and wiring and work backwards from there.
Ciao,
Adrian
964C4

PS: I still suspect the central electric. This cannot be excluded because of two similar cases I had some time ago (before these forums actually) with RSAs only and corrosion in the motherboard.