Temp gauge needle not moving

[meggles]

As title. Everything was fine when I set off. After around 15 miles the temp cauge needle dropped to the bottom of the scale. Duff sender? Can I short the wires briefly to test it?

[pirate-pete]

Thats right - short the wire from the sender to earth and you should see the needle move to full scale.

If that has no effect try jiggling the multiplug at the back of the cluster with engine warm and ignition on and you'll soon see the needle move if something loose there.

[meggles]

Had instrument panel off and ensured all connections are good and tight. I used a piece of wire to bridge the contacts on the plug for the temp switch. When I connected a wire to the live terminal and quickly 'flashed' it to earth I got a rather strong spark. Still no movement on needle.
2 questions:
1) Should the gauge move when I bridged the terminals?
2) Is there a way to test the gauge itself?
Thanks

[jeffj]

Keith

Had similar problem with my guage on Autosleeper. Followed the test procedure on Wiki and melted the ignition switch?

Mark told me how to check if faulty sender, will ask him to forward it to you.

Used his test system and proved guage was okay. Changed sender and all working again.

Jeff

[meggles]

Thanks Jeff, I'd appreciate that. Drove from Filey with no gauge. Had to keep heater on to make sure there was water circulating and it wasn't too hot (made me sweat a bit).

[meggles]

Still no reading!
To date I've done the following:
Replaced the sender unit/switch - No improvement
Bridged the connection on the plug - No improvement
Heard the relay in the 'box of connections' in engine bay click (also tried a known good one) - No improvement
Ensuree multiplug connections are clean and undamaged - No improvement
Took a live feed to a terminal on gauge itself - The needle moved.
Now I'm wondering whether the fault could be on the PCB (resistor?). Is there anything else I can do to try to track down the fault. I have a multi meter but do not know how to use it. And I don't have any instructions for it either. I was thinking of using a wire to temporarily by pass the resistor but I don't want to fry the PCB. Am I likely to do that if I bypass the resistor?.

[hefti]

had a similar issue just the other day, since im new to this camper van lark i have no idea where to even start to fix it myself. it dropped to off the scale then moves to the beginning of the scale when warm.... want to take the camper for its first overnight trip tomorrow is it too risky to do so when the temp gauge isnt working properly?

[meggles]

I drove over 40 miles with the gauge not working. Had to as I had grandson with me and needed to get home. I would NOT advise it. I kept the heater on in the hot position and as long as it was belting out heat I guesed I was probs OK. (and I was). However, gauges will often show different readings from van to van, so maybe yours just reads low all the time, and the time to worry is when it goes towards halfway. Just my thoughts on it.

[hefti]

i kinda thought the time to worry was when the light came on lol

[meggles]

i kinda thought the time to worry was when the light came on lol

Actually it's when the van fills with steam

AND the problem was: I forgot there are two senders on the thermostat housing A wire had snapped off one of the crimps. Some fool (not me this time) had put a couple of crimps on the wire in the past and not pulled the cover back over the sender. So.... all the messing with capacitors etc was not necessary. Thanks anyway for all your replies, esp MarkFoss for the texts
One final question: Why are there two senders?

[hefti]

Well after the fan belt snapping I can indeed confirm that our temp gauge does work all be it from a different position to when we bought it. Glad you got your issue sorted.