Club 80-90 Forums

Ok this is for my brother he has a 1988 1.9 DG and the temp gauge doesn't work.
We have just replaced the sensor with a new one but its made no difference.
Any ideas?
The thing is I can't see a needle at all,yet you can on mine(1.6d) even when cold.

lhd wrote:Ok this is for my brother he has a 1988 1.9 DG and the temp gauge doesn't work.
We have just replaced the sensor with a new one but its made no difference.
Any ideas?
The thing is I can't see a needle at all,yet you can on mine(1.6d) even when cold.

what happens when you put the wire to part of the engine ie earth it out ???

if you find the problem please update us as I cant manage to get mine working either.

I have chucked solder across the pins, changed the sensor and still get 0 volts at pin 6 on the socket into the dash, I have checked the temp gauge by joining it directly to the battery <- (sorry it said dash before) and it slowly rises. I do get 12 volts at the temp sender socket but somewhere along the line it is broken.

Can you see your needle on cold, like I can on mine.
I think his gauge is Kaput.

Well if the gauge rises slowly when you put a voltage to it, its working. It has to be a break in the wiring somewhere.

I will have to investigate.
Just spent two days replacing his exhaust, replaced all the coolant then just before bleeding all the air out he tells me he has no temperature gauge.

easiest way of solving this, is to run a newpair of wires from the sender to the multiplug at the bottom of the instrument pod, thus being sure it isnt the wires......

could also be the voltage regulator on the dash pod, but the gauge dropping right out of veiw suggests a connection problem to me

Clartsonly
You wrote,

I do get 12 volts at the temp sender socket

Look.... if your gauge works across a battery and you have 12 volts at one side of the sender plug.
(I assume this is with the gauge in its normal position, all the dash wiring connected and the ignition on).
Then check you have a good earth on the other side of the plug at the sender.

The current flow is from the battery positive through terminal 15 on the ignition switch, to 14/8... through the temp gauge to14/6... then to the sender (G)... through the sender (31)... and via T7a/4 and T7/7 to earth, and therefore to battery negative. Follow the wire and check each connection from the sender to earth.

This all from the Haynes diagram. The earth point is shown as 15 (Engine compartment under coil)

kin'ell you are hard work!!!
Mike

The current flow is from the battery positive through terminal 15 on the ignition switch, to 14/8... through the temp gauge to14/6... then to the sender (G)... through the sender (31)... and via T7a/4 and T7/7 to earth, and therefore to battery negative. Follow the wire and check each connection from the sender to earth.

pin 8 must be working because it is the main power to the clocks I know this as it is the one I have to wiggle to get them working again.

pin 6 has no volts when I use 20v on a meter between pin 6 and earth. ignition on and with the circuit bypassed.

I understand what you are saying about following the wire but it goes into the black box full-o-wire in the engine compartment and then disappears.

------

my understanding was that pin 6 should have volts, but it sounds like from your description that pin6 will only have 12 volts when it is plugged into the clocks, then the flow goes to the sender unit, which does get 12 volts but are you saying that the current is not completing the circuit?

my drawing...

[img:660:440]http://clartsonly.com/camper/diag.jpg[/img]

The loom side of the 14 pin connector when disconnected from the dash flexy printed circuit will not have any voltage on pin six as this should go to earth via the temperature sender.

The voltage comes from the flexy printed circuit side.

'Sender' is a misnomer, the thing receives the current from the gauge and shunts it to earth, the resistance decreasing as the coolant temperature rises so allowing more current to flow though the temperature gauge and causing the needle to deflect more.

If you have no earth connection on the opposite side of the 'sender' you will not have a circuit. Even if you short across the sender plug.

Mike

which is what I am confused about if I put one side of the multimeter into each hole in the temp sender connector I get 12volts, which would imply a closed circuit, therefore if the earth is bad I should not get anything, I will test it again incase the new temp sender is faulty.

It could still be that you have a poor earth connection somewhere as I suspect that because the multimeter has a high resistance very little current will be passing through it, and it may therefore indicate 12 volts.

Just short the gauge side of the sender plug with a bit of wire to a nice clean earth and see if the gauge goes full scale.

Mike

okay, which is the same issue I had with the radiator fan, it showed volts but no current I will try what you have said possibly tomorrow. I am packing the van tomorrow night for a night away in sunny norfolk

lhd wrote: The thing is I can't see a needle at all,yet you can on mine(1.6d) even when cold.

My gauge was like that when I got my van (1.9DG). Took the gauge out of the dash and the needle was missing Replaced the gauge, still not working. Checked temp sender and that was fine, no breaks in wiring either.
Turned out to be the plug behind the dash. All the other instruments worked fine except the temp gauge. In the plug are thin spring contacts that match up with the contacts on the flexi circuit, I noticed one was flatter than the rest so, with a precision screwdriver I carefully lifted the contact to the same height as the others. Then I lifted them all slightly more to give a tighter contact on the flexi circuit.
Took me ages to find it, more luck than anything

arrrrhhh.

the earth under the coil looks like it is maybe going through painted tin into wood, the bolt is rusty like the connectors, I cant sort it out tongiht though and am going camping tomorrow norfolk way. It looks like someone has tried to find a good earth around the whole area then simply gave up. hopefully this may solve my problem... but how many extra problems is it going to introduce once all these components are suddenly earthed???