ad53030

I'm trying to wire up the a/c in my 84 w/ a 5.3 from an 07 Silverado. I wanted to reuse the factory low pressure cutoff switch on the dryer. There are two wires coming out of the switch - one + 12v & a second that should complete the circuit and activate the switch. My question is where should that lead be wired to? I was told to connect it to the relay for the a/c comp but I don't know which of the four terminals to connect to. I'd rather wire it into the relay than directly to the compressor as the engine harness is factory and I have a relay center near the ECU (as wired by current performance wiring).

N21923

iTrader: (8)

What ECU are you using? Are you using DBW or cable?

ad53030

Using stock 07 truck ECU (DBW).

fast400

iTrader: (1)

The low pressure switch should have (-) voltage on both prongs. It simply completes the negative circuit to the compressor once the switch closes (pressure is good)