I'm piggybacking terminator x in my 99 z28. So I removed wires I didn't need out of original harness. Stuff like injectors, coils, sensors, that terminator replaced. But I left coolant temperature sensor. Now in hptuners and dash coolant guage is reading. In hptuners scanner i can command each fan to come on. But why will ecm not command it when temperature is high enough

 

Best I can find is that the computer must think the car is running before it will turn the fans on. Any way to trick the computer into thinking the car is running

 

Thinking it's running, or actually running? It shouldn't be real hard to do, but without knowing exactly what you've done wiring wise, it might be hard to say.

 

Thinking its running. I've got factory alternator wire hooked up. Factory temperature sensor. Vss hooked to abs sensor in front wheel bearing. Engine has 58x crank so I can't split it factory computer needs 24x

 

Have you set everything right in the software on your Terminator??

 

I'm trying to run the fans off the stock computer. In hptuners I can turn them on using the scanner. But car will not turn them on itself. Temperature sensor hooked up and guage works fine.

 

Do you have the crank signal still going to the stock pcm? Its needs to see rpm and temp for the fans.

 

Just use one of the I/O on your Holley setup. Set to a ground trigger and bobs your uncle. Then you can set it to any temp on/off you want. Seems like your making things more difficult than they need to be

 

Thats what we do but I didnt know if he was trying to save outputs or something why he was using the stock pcm.

 

Yea it's pointless to be using the stock pcm he's paid for a Holley efi system that can do all of that and more. I bought an HP unit way back when they first come out and couldn't rip the stock stuff out fast enough