Sorry for another temp gauge question!

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Ads1987
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Joined: 06 Nov 2012, 22:11
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Location: Golden Green, Kent

Sorry for another temp gauge question!

Post by Ads1987 »

Hi Peeps,

Sorry for another temp gauage/LED question, have been reading through the WIKI and things but thought i'd check before I buy a relay!

We have a 1.9DG early van with the 43 type coolant relay, the coolant LED no longer flashes on start up and the temp gauge has stopped working. I checked the wiring to the sender and the sheath was damaged which had exposed to wire and caused corrosion, so cut this was out and re -wired. Sometimes very briefly when you turn the ignition on you can just see a tiny glimmer of the coolant LED and then nothing, so gauge stays at the bottom and no flashing. Removed 43 relay but seems to have no effect on the system.

Have a Sealey power probe, this shows continuity at the temp sender on thermostat, at the yellow/red wire on the relay and also at the instrument cluster pin housing, the small nut on the PCB is tight. If I remove the connector on the temp sender I loose the continuity light on the probe at the cluster multiplug yellow/red wire.

So it seems like the wiring is ok, before I buy a new 43 relay is there any checks you would carry out?

Thanks for your help,

Adam.
1982 T25 1.9 DG model with 4 speed box

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AngeloEvs
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Re: Sorry for another temp gauge question!

Post by AngeloEvs »

This does not sound like a module 43 issue. The temp gauge is fed with a 10v supply from the voltage stabiliser and this provides the voltage for the temp gauge internal circuit to cause it to flash. This circuit will function with or without the module 43 fitted but not if the 10v supply is missing or if there is a problem with the circuit in the guage.

The temp gauge will also stop working without the 10v supply.

I would first check that there is 10v at the guage itself. The gauge is secured by three nuts which connect the gauge to the membrane circuit, check that these nuts are tight, they can become loose. There should be around 10v on both the larger nuts, the small centre nut is the temp gauge earth (0v) connection and this also needs to checked for good continuity to the vans earth.

You did not mention the fuel gauge, this is also fed by the same 10v supply so my guess is that if the fuel gauge is working then the most likely problem with the temp gauge is a lack of 10v getting into to gauge itself.
1987 DG Karisma LPG with remodelled interior

Ads1987
Registered user
Posts: 191
Joined: 06 Nov 2012, 22:11
80-90 Mem No: 13081
Location: Golden Green, Kent

Re: Sorry for another temp gauge question!

Post by Ads1987 »

Hi AnegloEvs,

Thanks for your help, the fuel gauge seems to be working fine which is what lead me to believe the fault lied with the relay as most people say the fuel gauge fails at the time as the temp because of the regulator.

The nuts were tight but I'll find my volt meter and measure the power supply to the gauge, the small centre nut was the one that lost continuity when the plug was removed the temp sender.

Cheers,

Adam.
1982 T25 1.9 DG model with 4 speed box

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