should both heaters come on all the time, or just one until it is colder outside ?

both relays cycle when testing them, but when they are connected up in the normal circuit, only 1 comes on (and I don't think it was until I cycled it using jumpers)

1 relay doesn't seem to be cycling using it's trigger wires, but if I move the trigger wires from the other relay, it does.

 

OK...here's what I have right now

air temp sensor is bad...reads open

I have a 97, so the 12v trigger wires are both bk/gr, and the trigger wires for the ground from the pcm are yl/bk & or/bk.

one of the gr/bk wires has 12v to it, the other doesn't.

neither of the trigger wires from the pcm show as a ground when the key is on. this may be due to the bad air temp sensor.

Why would I have 12v to only 1 of the gr/bk trigger wires ?

 

This may help http://dodgeram.org/tech/dsl/trouble...niford_htr.htm

 

already looked thru that link

it says the wait to start light won't come on above 60 deg, and mine has always come on for more than 2 sec

anyway...1 or the ford relays I have now is acting weird, so I just ordered the relays and a new air tmp seonsor from rockauto.

when they get here, I'll try to figure this out more...heck, I may just put a manual switch in