Page 1 of 1

Temp Gauge Sender Resistance Range

Posted: 14 Aug 2015, 11:38
by T25Convert
Hi all,

Early DG engine which seems to be running fine, but often temp gauge is showing cold even on a long run, suggesting failed open thermostat. However, you can still get hot air out the heater, suggesting its not as cold as the temp gauge says it is!

Does anyone know what the resistance should be of the temp sender on a warm engine? Would enable me to make a quick check its not wiring related before I start the thermostat replacement!

Cheers,

Alex

Re: Temp Gauge Sender Resistance Range

Posted: 14 Aug 2015, 11:53
by MidLifeCrisis
You could just ground the connector that goes to the sensor - that should make the gauge show 'full hot';
Or here are the approx ohms values to move the gauge .... (You need columns 2 and 5)
Image

Re: Temp Gauge Sender Resistance Range

Posted: 14 Aug 2015, 13:30
by ghost123uk
Failed temp senders, reading too cool, seem quite a common thing in my experience. I must have gone through 4 or 5 in my (~11 year) ownership of T25s.

Re: Temp Gauge Sender Resistance Range

Posted: 14 Aug 2015, 15:25
by T25Convert
MidLifeCrisis wrote: Or here are the approx ohms values to move the gauge .... (You need columns 2 and 5)

Many thanks for this, great help.

Cheers,

Alex

Re: Temp Gauge Sender Resistance Range

Posted: 15 Aug 2015, 08:01
by Aidan
disconnect the wire from the temp sender and put that to earth and turn ignition on guage goes full hot and flashes led, if it doesn't then it is a wiring fault, probably corrosion at temp sender connector or 14 pin multiplug issue/connection to circuit borad