I’ve got my haltech all setup and running currently setting up an IAC and haltech controlled fan relay I wanted to do the same with the A/c compressor.

would anyone be able to assist me with figuring out in the A/c wiring where the request signal is? Maybe I’m missing something but this is my goal

“Wire the 22RE's A/C Request signal from the cabin switch to a spare Analog Voltage Input (AVI) or Digital Pulsed Input (SPI) on the Haltech.”

I am assuming once that is located, I should be able to find the ground side of the compressor relay pretty easily to setup a DPO

any help is appreciated

 

Can I assume a "haltech" is a replacement ECU? https://www.haltech.com/ecu-buyers-guide/ In your stock truck the AC isn't controlled by (or even connected to) the ECU. Are you just trying to replace the on/off switch? I know nothing about "haltech," but I don't see that their ECUs have an output for that.

 

haltech is a standalone ECU and it can do other functions/switches/sensors. It can control A/C clutch and in this instance it can apparently just control the A/C relay and leave the amplifier in tact I just can’t decipher the diagram to find what I need