cooling fan failure - Solved!
06-07-2009, 03:19 AM
#48
Addict
Rennlist Member
Rennlist Member
Join Date: Feb 2002
Posts: 5,384
Likes: 0
Received 0 Likes
on
0 Posts
I guess this is now a myth buster. The low temperature sensor on the radiator makes the fan run after the ignition is turned off, not the high temperature sensor.
Chris, lots of credit as to go to cruise98 for pointing out the radiator high temp sensor is in parallel with the AC temp sensor. You can find all you need to know by testing the fan relay terminals.
Chris, lots of credit as to go to cruise98 for pointing out the radiator high temp sensor is in parallel with the AC temp sensor. You can find all you need to know by testing the fan relay terminals.
Last edited by Bri Bro; 06-07-2009 at 07:24 PM.
06-07-2009, 02:17 PM
#49
Rennlist Member
I guess this is now a myth buster. The low temperature sensor on the radiator makes the fan run after the ignition is turned off, not the high temperature sensor.
Chris, lots of credit as to go to cruise98 for pointing out the radiator high temp sensor is in parallel with the AC pressure sensor. You can find all you need to know by testing the fan relay terminals.
Chris, lots of credit as to go to cruise98 for pointing out the radiator high temp sensor is in parallel with the AC pressure sensor. You can find all you need to know by testing the fan relay terminals.
I'm less familiar with the A/C pressure switch circuit, but are you saying that switch activates the high speed fans? That would be curious, since I thought the fans come on in low speed when the A/C is turned on.
06-07-2009, 02:31 PM
#50
Addict
Rennlist Member
Rennlist Member
Join Date: Feb 2002
Posts: 5,384
Likes: 0
Received 0 Likes
on
0 Posts
Yes, the A/C temp switch turns on the high speed fans. So when you turn on the AC switch the fans are at low until the pressure switch goes active, then they run at high. You can try it out by turning on the ignition and pressing the AC button. Both fans will run at low. Now start the car and press the AC button, the fans will go to high if the AC system is working.
Last edited by Bri Bro; 06-07-2009 at 07:22 PM.
06-07-2009, 06:40 PM
#51
Addict
Rennlist Member
Rennlist Small
Business Sponsor
Rennlist Member
Rennlist Small
Business Sponsor
Thread Starter
BTW – the sensor/switch is referred to as the “Refrigerant Temp Switch” in the wiring diagram and it is in parallel with the high temp fan switch.
The switch was actually fine, it was the wiring harness that had the fault - so testing the switch did not flag the fault!!
The switch was actually fine, it was the wiring harness that had the fault - so testing the switch did not flag the fault!!
