No rev counter when headlights are on

[Ryan]

So on Monday with the tax quickly running out, I set off in the Storm to drop it at the bodyshop (at last).
It must've known someh=thing was up...

Going up the A34 I decided to put the headlights on as it was pretty overcast... and the rev counter died.
Now it sometimes goes through phases of being really bouncy - with the needle wildly reacting to any bump in the road.
but it's never completely died before.

I turned the lights off straight away, and it jumped back to life... turned them on and nothing.

So I carried on for about 10 mins until I got to the bodyshop, and as soon as I turned off the main road, I switched the lights off.

Rev counter was back straight away, but then I notice the water temp needle spring into life (which I missed dying prevously)
Then the red light starts flashing for the temp as it continues to creep up.
Parked up, kept the engine running and popped the bonnet to check coolant level, which was a bit low, but not worrying.
20 seconds later the fan kicked in - but the warning light was still on.

Tuned it off and gave the bloke the keys!

Anyway, any ideas what it might be?

[81GTi]

could be some sort of short at the back of the clocks. maybe around the voltage regulator for the temp gauge, i would check the lead from the coil to the rev counter before taking the clocks out, give it one of them technical wiggles and see if it is any better...

ps got your PM cheers

[Turbogirlie]

Have you fixed it yet?

Had similar problem with the GTX a while ago. Lost the speedo, rev counter was out, fuel gauge misreading & lights flashing on the dash - great fun!

The earthing wire off the rocker box cover had broken.

New, longer wire, all sorted!

[Ryan]

Can't look at it for a while as it's in the bodyshop

[Turbogirlie]

Fair enough! The more I think on it, the more it sounds like the earth problem I had. Everything worked fine until I put the lights on, even on parking light.

Let us know how you get on once she's back from the bodyshop - what are you having done there then?

[Ryan]

what are you having done there then?

The works

[Turbogirlie]

Nice one!

You won't regret it - had a heap of work done to my GTX - had her back on the road for 2 yrs now & still lovin every moment!

[Mr Funk]

Can't wait to see it next year.

[Nate]

my scala did this. the earth lead from the coil to the top of the engine was loose

[Ryan]

my scala did this. the earth lead from the coil to the top of the engine was loose

Cheers, I'll check it out when I next go up there.

[mark1gls]

When my Golf had the same problem I could get the rev counter to read 1/2 the amount of revs by dimming the dash lights, turned out to be a broken earth wire from the dash. I would guess its an earth wire some where.