Buzzer - what is it telling me?

[marcus]

Having solved my no-spark problem, now when I turn the ignition on without starting the engine, a buzzer in the instrument panel goes off after a minute or two. Wasn't doing it the last time I worked on it, only change is I've replaced the ignition switch shroud and re-seated the fusebox in its holder...

Reading the instruction manual it seems intended to warn of low oil pressure though I see no sign of it in the Haynes wiring diagram, unless it's included in the 'oil pressure monitor monitor control unit' in track 29.

[Nate]

Yup, the buzzer is telling you to switch off the engine due to lack of pressure. Buzzer sounding with the engine off would suggest something is broken

[marcus]

One of those really annoying things that goes away without you knowing why... maybe an intermittent poor connection somewhere, removed and re-seated the fusebox, detached and reattached the blue/black wire connected to the low pressure sensor in the cylinder head (that was the one causing the issue, when disconnected the buzzer stopped but when reconnected the buzzer didn't restart).

Anyway, I'm loving the car starting first time though, ignition module must have been on it's way out for a long time.

[mark1gls]

The buzzer should only go off if the engine revs are over 2000 rpm and low oil pressure, if its going off with out the engine running there problerly a fault some where else.

[the edmundator]

I think this is a common fault, especially on earlier (pre-'84) cars. I had an '82 GTI which would intermittently buzz as you drove along. Sometimes it would stop if you hit the dash. I expect it will be an electrical fault of some sort.

[ianaudia4]

Oh it is very common when the oil pressure switch gets old and becomes porous! My Storm had the same sympton, easy fix, changed the switch and nothing since, I think the switch cost about a tenner from VW.

Also check that the sleeving on the wiring to the switch hasn't degraded to the point of being bare!