Coolant level/temp flashing light

[Matt and Danni]

Hello, I hope everyone's had a nice Christmas!

1.6 diesel CS engine

I have a bit of an issue with the flashing LED for the coolant level/temp, as many other people have it seems!

It appears a bit different to other threads I've read, as the light doesn't appear to flash when the coolant level is low..

It flashes when the ignition is on, then goes out when the engine is started. The light flashes up to the point the engine is started, not sure if this is right as I read in the wiki that it's meant to go off after a few seconds of flashing.

I've cleaned up the prongs on the coolant level sensor and the earths behind the glove box, to no avail.

Has anyone experienced anything similar?

Thanks

Matt

[Hacksawbob]

The flashing on start up doesn't tell you that much other than the light is still working. There is some crazy (but clever) AC current that the relay shaped box tests for coolant level making it hard to test in a straight voltmeter DC kind of way. AngeloEVS is the level sender guru read his expanation here. https://club8090.co.uk/wiki/Co ... ht_on_dash" onclick="window.open(this.href);return false;
if you have checked the earths in the cab area make sure you also check the earth in the engine bay It's under the air filter on the engine side wall a diesel! you may find your rear lights shine brighter too! (I rewired them all back to the Neg on the battery as the connection there was rotten.

[MidLifeCrisis]

Matt - correct me if I'm wrong but I think what you are saying is that with the ignition on (but engine not running) the led flashes all the time (i.e. it would normally only flash for about 5 seconds then stop). Then when you start the engine the flashing stops.
If this is what you are saying then 'yes' I have had a similar issue - I never really figured out what was going on (as my issue was intermittent - sometimes it would behave like yours, sometimes it would work fine ...) so it was hard to diagnose.

One interesting test would be to pull (remove) the 42 relay (or is it the 43 relay) that does the coolant level test and see if that makes any difference - that might at least narrow down the problem.