Jaguar Repair: E type fan relay, temperature guage, jumper wire

Question
Hi Howard, Rory here again working on the 70 series 2 e type.  The thing is overheating from time to time.  I noticed that when the temperature guage gets to the red, my fans are not running.  If I bypass the otter switch attempting to keep the fans running, they still don't run......otter is good.  If I let the car sit for a day and cold with the otter still bypassed, I turn the key and the fans run just fine.  It seems that when the engine gets warm, the fans fail.  Could that be the relay?  There are two relays just behing the fans.  Not sure which is which.....thought?  Many thanks as always.....Rory

Answer
Hi Rory,

If you have two relays that means you have AC but the system operates even if the AC relay don't.

The wire from the fans is black w/green tracer to pin "C-1" on the fan relay. Power from the fuse box comes to pin "C-2" with a green wire. The thermo switch called the "otter" switch grounds the relay to make it operate when the coolant is hot. (Black w/red tracer wire)

To test the system when it has failed (it is no use testing it when it is working) just confirm that you have power on the "C-2" terminal (green wire) then confirm that the "W-1" terminal (black w/red tracer wire) is a good ground with a jumper wire.

If both of these are correct then test "C-1" for power. (the out put from the relay) This way you know for sure what is wrong.

Howard