Strange problems, help/advice needed please

[Yaz]

Hi all,
I thought I would post this on here in case anyone knows or has had this issue before. I recently picked up my A100 2.8 Quattro 1992 and briefly drove it for the first time on Saturday after it had been laid up for nearly 3 years by the previous owner. The car has been fully MOT'd and serviced etc, so it ran very well. I was overall very impressed!

But there are two issues.

First I spotted that the speedo doesn't seem to be in sync with the speed I was actually doing. I first noticed this when I joined a dual carriageway (50mph limit) and was approaching a speed camera. I glanced down at my speedo expecting it to show in the region of 50mph but instead it was reading about 30ish mph!
Any ideas?

Second fault is that the hazard lights appear to be flashing continuously regardless whether the car is locked/unlocked or when the engine is running. If you then pressed the hazard light switch to turn on you can see a irregularity in the light flashing but they still continue to flash.
It looks like to me that the alarm is triggered, but there is no alarm sound.

Has anyone come across this before?

Any help or suggestions is greatly appreciated!

Many thanks
Yaz

[UrS4boy]

... The car has been fully MOT'd and serviced etc, so it ran very well. I was overall very impressed!...But there are two issues. First I spotted that the speedo doesn't seem to be in sync with the speed I was actually doing. I first noticed this when I joined a dual carriageway (50mph limit) and was approaching a speed camera. I glanced down at my speedo expecting it to show in the region of 50mph but instead it was reading about 30ish mph! Any ideas?

Strange that it passed its MOT with those issues.

Anyway here is some info that might help with the first issue:

G22 VSS/G21 Speedo info: http://forums.quattroworld.com/s4s6/msgs/168463.phtml

C4 instrument cluster readout (might or might not be the issue):

There is an adjust switch on the back of the instrument cluster:
(Instrument cluster removal: http://12v.org/faq/c4/instrument_clu...eplacement.htm )

For the six-position switch on the left side of the photo below, the switch positions are about countries and fuel type. (Ignore the number of cylinders comment - it is wrong)

Switch.... Country/Fuel
Position

...1......German speaking countries/gasoline
...2......USA/gasoline
...3......All other countries including Canada/gasoline
...4......German speaking countries/diesel
...5......USA/diesel (Which is funny since no US C4 diesels)
...6......All other countries including Canada/diesels

[andy10v]

Second fault is that the hazard lights appear to be flashing continuously regardless whether the car is locked/unlocked or when the engine is running. If you then pressed the hazard light switch to turn on you can see a irregularity in the light flashing but they still continue to flash.
It looks like to me that the alarm is triggered, but there is no alarm sound.

Does it have an after market alarm or the remains of one?

[bluequattro]

Are you locking with a key or a clicker?
My urs4 played silly beggars as I'd tried start it with a different ignition key/switch as the original had failed
Locked car with proper key, put it in ignition to cancel factory immo and lights stopped flashing
Has the alarm horn been disconnected?

[Yaz]

Hi peep, thanks for the replies.

UrS4boy - thank you for the info with regards to the speedo issue, I will take a good look at this. The only issue with this and the MOT would have been the hazard lights flashing, but this can be stopped using the key in the passenger door which seems to stop it. But as soon as the drivers door is touched then the hazards seem to stay on continuously

Andy10v & bluequattro - we (my dad and I) discovered that there was an aftermarket alarm siren to the left of the engine extremely close to the manifold and the wires had been cut. So I reckon the alarm was being triggered and someone has chopped the wires. Then we followed the wires to below the dash under the steering wheel where we found a 'Sigma' box. We then disconnected this and the problem with the hazards lights has now stopped and the indicators work as they should
The central locking is now not operational but that would be down to the wiring to the Sigma box that we would need to repair.

The keys are the chunkier type with a single button that just operates the light/torch I believe, but that doesn't work anyway...

When I lock the door with the key I can hear the horn chirp at the back as normal.

But it looks like Andy hit the nail on the head regarding the aftermarket alarm.

Thanks for your helps guys, hopefully we're on the final straight with getting this car back on the road!

[andy10v]

I got an 80 that was the same, after market alarm with the sire cut so it just flashed, thankfully it was not an immobilizer.

Have you traced all the wires from the "sigma" box? Some will probably go to either side a cut in the OEM wiring.

[Yaz]

Hi Andy, not yet but I'm planning on doing some more work on it this weekend.

I got an 80 that was the same, after market alarm with the sire cut so it just flashed, thankfully it was not an immobilizer.

Have you traced all the wires from the "sigma" box? Some will probably go to either side a cut in the OEM wiring.