again, how did you jump the relays?

 

thats how i jumped the relays..

 

ok, check for power at the brown wire at both fan relays

 

I had the exact same problem on my 88.
couldn't get niether fan to come on. Even when the temp hit 260, neither fan would come on. If I pulled the A/C press connector, the secondary would come on and the primary for a sec.
I just wired up 2 switches to the grounds on each relay to control each one individually.

Then I did an Auto to T5 swap and about a month later I decided to change my prom settings to a manual and I lowered the fan temp for the heck of it.
My fans (at least the primary one) started working after that.
I don't know if it was the prom or the ECM wires since I had to move them to pull the ECM out, but it all works fine now.

 

Yeh, on vin "E", throttle body injection.
All vin "F" and "8" have none..

 

This is the Temp sender for the gages, disconnect it and it should bury the needle.

 

nope ive got that sensor on the driver side of my block....its got a slip fitting on it....connection just slides onto it

 

nope, all the TPI diagrams too, havent even looked at the TBI ones

 

have you checked the brown wires yet?

 

1992, Primary cooling fan IS controlled by the ECM, period, nothing else.

There IS , however, a switch (gray wire) there for the SECONDARY (H/D) cooling fan that DOESN'T come on until 238+*, in parallel with the A/C fan/pressure switch. (On the A/C diagram)Which has it's own separate relay too.
My aftermarket chip was programed to turn on my PRIMARY fan at a lower temp than the stock setting. Replacing that switch does little to run cooler.

 

When your car is at roughly 205-210*, the ECM will energize the dark green wire with the white stripe at the relay. If it never gets voltage, either the wire is damaged or the ECM/PROM is bad.

 

Actually, the ECM grounds out that wire. There should be power at the relay when the ignition is on.

 

if you look back over my posts, I said that the primary was controlled by the ECM, and the secondary was controlled by the switch and the A/C pressure switch, you kept saying there was never a fan switch on a 92,
you need to make up your mind


he has said that neither fan comes on, so, unless he has 2 different problems, he needs to look at the things that are common to both fans, so, I am still waiting to here if he ever checked the brown wire at both relays for power

 

ill check that wire in the am and post how it goes..

 

If you read my previous post, you will notice that I had the same problem.