Club 80-90 Forums

My Temperature Gauge Flashing light has started playing up again....
Sometimes it flashes and goes out , others it stays flashing for ages or doesnt go out at all...

Ive checked all the usuall things (water levels / wiring temp sender etc) and removed the lscu and the issue is definitely in the dash / temp gauge somewhere.

Ive got the dash pod with the gauges in it on the bench now and wired it up to 12v at pins 7 and 9 of the 14 pin multi connector (clock gauge centre and voltage regulator) and ground to pins 2 and 5.

Clocks working and the temperature light is flashing continuously. Ive got a steady 10V at the regulator out.

Now in my van it would do this also but sometimes the light goes out if I start the van up !? Should it go out before starting the van?

Do other peoples temp lights flash until started or go out with in a short time if left with ignition on but not started?

after switching on the ignition it should flash for a short time and then go out, whether or not it the engine is started.

Try pulling relay 43 - not a fix but part of the diagnostic process (least it was on mine!) - and see what it does then. On my 1.9dg it flashes pre-start and goes out once running (I think - I'm not at the van at the moment!)

Post by marlinowner » Yesterday, 23:32

after switching on the ignition it should flash for a short time and then go out, whether or not it the engine is started.

Thats what I thought as i cannot see anything in the circuitry that informs the gauge that the engine has started!? What year / model is yours as I believe there are 2 dashes and it may be different from mine?

LeeME3 can you verify that yours goes out only after starting? ( allready removed relay 43 and it made no difference)

I've just double checked and yes the light stops flashing whether or not the engine is started. My van is actually a 1993 SA one, but the instruments are out of my old 1989 DG van.

cheers marlinowner -

can anyone else confirm what theirs does? (Just want to make sure there aren't 2 different dashes out there that behave slightly differently)

Shaundon wrote:cheers marlinowner -

can anyone else confirm what theirs does? (Just want to make sure there aren't 2 different dashes out there that behave slightly differently)

Yep - the led should flash for a few seconds when it first gets power (i.e. when you turn the ignition key) then stop flashing.
This behaviour can start to fail as there is a capacitor in the gauge that controls how long the light flashes for and if the capacitor is broken or degraded then the light might continue to flash for a while or permanently as you have seen.

The capacitor can be changed (if you are handy with a soldering iron);
Have a look at this topic ....
https://club8090.co.uk/forum/viewtopic.php?f=39&t=126504

You say that you have confirmed that the 10V supply at the voltage regulator is good - have you confirmed that the 10V is still good at the gauge terminal?
Then have you also confirmed that the ground terminal of the gauge is seeing a good ground?

cheers - picked up the capacitor at maplin today - gonna attempt this tonight

Way hay - I now have a working temp gauge light for the first time ever - put the new capacitor in and it flashes for a few seconds before going out even before turning over.

Top tip to remove the capacitor from the top side - i spent ages trying to remove the board but couldnt get it out, perhaps if i had a better desolder pump but after reading your posts MidLifeCrisis I got the cap out from above and just added the new one above.

Before this it always required an engine turn over to turn the light out and this was touch and go at that. Interestingly I managed to simulate this on the bench with the faulty gauge by dropping the voltage to the gauge temporarily to simulate turning over and it did turn the light out. So if you require to turn over to turn off your light youve probably got a faulty gauge and need to replace your capacitor....

Good stuff - glad you got it sorted.
I also tried to get the board out but pretty glad that I didn't in the end cos I imagine you'd probably end up breaking something fragile in there getting it out?!?