Club 80-90 Forums

My van is doing a strange thing, I'm getting the red temp light flashing when I put my headlights on, there is also a slight drop in revs when the headlights go on so probably a significant voltage drop. When the headlights are switched off the flashing red light stops everytime, van tested when its up to temperature. Its an early van and my coolant level is good.

Following recent charging issues I've fitted a new battery, had my alternator checked out, new voltage regulator, new main earth strap and cleaned up battery and coil earths. The main battery to starter cable is recent with good, clean connections. The battery to dash cable looks original.

Does the red temp light behave correctly when switching the ignition on ?

It’s a bad earth !
You could also try taking the relay out for the coolant warning ( up above the fuse box near the earth crown) numbered 42 or 43 , and check the contacts are not corroded and manky

Thanks for the input, the red light behaves as normal when I turn the ignition on, it goes out after a few seconds, will check the earth's tomorrow.

Double check you haven’t got a side light bulb out - my high beam light came on when I switched my lights on and it was down to a blown side light bulb.

Thanks, I've checked the earth's at the dash and all seems good. I'm now getting the flashing light and a rising temp gauge which I've had before, I think my header to expansion tank connection is toast. Might be time to replace the header tank with an upgrade.

Chack what module you have - I suspect it is an early "tall" type 42 module, which sends the temp gauge to the right as well as flashing the light. The later type 43 modules don't do this.

Check the water levels in both tanks at the rear, top up as necessary, and make sure the connectors for the low level gauge are clean and in good condition

It's a 42 so the temp guage goes straight to the right when the header is low. I've repaired the hose connection before as it was bodged when I bought my van. Once the header is topped up the issue is solved, time to do a more permanent repair.