Oil Light, and Airbag light both coming on.

[hitman66]

My daughters 1999 Beetle 2.0 five speed has a strange issue with the Air bag light and the oil alarm and light both coming on at the same time, as well the Tachometer all of a sudden stops working. Everything seems fine then all of a sudden the oil alarm will chime, the light comes on, the air bag light comes on and the Tach drops to zero. I have warned my daughter about the oil light so the first time this happened she quickly shut it down and checked the oil, it was full. She then called me and I went to town and started it myself. everything was fine so I took it for a drive. After about five minutes the alarm came on and the lights came on and the tach died. We took it home I had a look for anything obvious but I couldn't find anything. It happens quite often now, does anyone have any ideas for me to look at.
Thanks in advance, Guy

[hitman66]

I am Still waiting for some Ideas so I can get started, if you have anything please reply because I am stumped.
Thanks again

[Smileybug]

Sounds like some sort of wiring problem. Maybe a grounding issue? You might want to see if any codes are thrown though. Most auto parts stores can scan for free and tell the codes.

Also, as an FYI, the oil light is not for level, but for pressure.

[VWBubba]

I am with SmileyBug on this one. Seems to much of a coincidence to be anything other than a wiring fault.

Airbag is normally a loose/faulty connector under one of the front seats but when this happens it tends to stay on until sorted.

Oil pressure is usually a pump problem or faulty sender unit, can be intermittent.

Tacho tends to be electrical and can also be an intermittent signal fault.

I would doubt the fault codes would help identify the cause, just that something is wrong. Check along the wiring harness where possible, look for breaks/chaffing. Check ground connectors, especially to the engine as two of these are connected there.

If you find nothing, it's a job for an Auto spark I am afraid.

Well done to you daughter for stopping when the oil light came on, better to be safe than sorry.

Before I forget, it may be possible, once the fault has shown itself to trace it by having someone sit in the car to watch the dash while you wiggle, poke, prod around the wiring harness, fuse/relay box, earth mounts, under dash harness and the like. If the tacho jumps or drops off, the lights flicker or go off/come on .. You are somewhere near.

[woofster]

As mentioned already, it sounds like it could be a grounding issue but it also sounds like it could be the beginning of a dying alternator.

[hitman66]

Thanks people for the ideas, I have a scanning tool to check for codes but there are no faults showing up when I scan it. I do not have the VAG Com scanner though and I'm sure that would give me a better reading. As far as standard error codes i am getting nothing. That is an interesting Idea about the alternator though, why would a dying alternator cause these kind of issues. How do I go about checking my alternator?

[Smileybug]

You can take the car to autozone and the like and they can test your alt for you.