Thread: Found the answer, CANT FIND THE POST!!!

Was looking thru my manual the other day and I found an answer to a post someone had re thermo fan running for 10 minutes after the ignition was shut off.

Basically the test procedure was checking the relay to see if it and the ECU timer circuit worked by removing the two connectors from the switch on the thermo housing and the plug from the fuel thermistor on the fuel rail and bridging both, turning on the ignition for at least 5 seconds the turning it off.
If the fans ran when ignition was turned to off, then the circuit was good.

This would then show that if connected normally when engine was cold, the condensor fans running when switched off raises a fault at either or both sensors.

This can be answered with a multimeter and a cold engine.
First, remove the thermo switch plugs on the housing, put your meter on continuity check and see if it closes circuit. You can do this with a normal pen type circuit tester fitted with a globe also.
If you get a light or closed circuit when cold, the sender is knackered.

Second, and you will need a multimeter for this, test the fuel sensor switch for its resistance with the meter set on ohms.

resistance /temp figures are as follows and apply to FUEL temperature

DEG C - OHMS
0 ------ 9100-9300
20 -----2400-2600
40 -----1100-1300
60 -----500-700
80 -----300-400
100 ----150-200

These figures also apply when testing the temp thermistor on the LH side of the intake manifold output too! (one on top with the plug)

If the readings dont correlate with this, then your fuel thermistor is faulty.

Although it doesnt state at exactly what reading the fuel thermistor needs to be at, the std thermo housing switch temp is 100 C.
I have changed mine to one that comes on at 90 and off at 80 as I use mine to run the twin 13" thermofans from the original condenser fan wiring and I removed the std condenser fans as they are rubbish anyway. As such they come on from engine temp and also with the A/C plus from a manual on switch on the dash, but I have never had mine run on after turning off the ignition.

If a mod can find the post I am referring to, please copy this to it or move it so the original poster can find THE ANSWER!!!

regards

Andrew

should go in the good oil