Temp gauge woes

aussie pete · Post by **aussie pete** » Tue Apr 12, 16 5:54 pm

On the charger (vh 770), that I am working on (yes its taken longer than planned !!!!) the temp gauge goes all the way over to the right (hot) as soon as the ignition is turned on.
Tested voltage at the sender.....12v
Replaced sender in manifold.....no change
Tried a spare gauge....no change
Previous posts state that the gauges run at 5v and needs a voltage regulator/limiter, however the factory workshop manual mentions nothing of this and spare parts that I have lying around show no evidence of it either,......any suggestions?

Dave999 · Post by **Dave999** » Wed Apr 13, 16 4:04 pm

no the 5 volt malarkey is a US thing

temp sender sits in head on a hemi 6 car

I always presumed 12 volts comes out of the gauge

and the senders resistance dictates where the needle sits

I think you have a short in your sender wire

no resistance = 12 volts through the gauge and full swing to HOT.

OR

it works the other way and you have a problem with one of the 2 bulkhead connectors. i.e full resistance = HOT

think the sender is through the one which also has the wiper power through it

Dave

aussie pete · Post by **aussie pete** » Wed Apr 13, 16 7:55 pm

Ok I have now sorted it, I was convinced that it needed a voltage regulator, thanks Dave for steering me away from that idea.Further investigation and it became apparent that the temp gauge casing was'nt earthed.Wonse it was earthed the temp gauge came alive,.

Dave999 · Post by **Dave999** » Wed Apr 13, 16 8:19 pm

ahhh

dash out
indicators don't work
guges don't work

driving lights work
windscreen wipers don't work if the switch isn't earthed

its a bit of a mine field

the only things that always seem to work are the horn and the ciggy lighter feed

hence the sparks