[StorminMatt]

I’m currently in the process of doing an E-Rod swap in my S13. This is a ‘California smog legal swap in a box’ sold by GM, and includes an LS3, wiring harness, ECU, cats, etc. Compared to other GM ECUs, the E-Rod ECU seems to be very ‘stripped down’ and ‘standalone’ - it doesn’t seem to have any kind of controls for A/C. This means that I need to run the A/C without any kind of ECU.

Now in the S13, there is a lead coming off the A/C amplifier that goes to pin 44 on the S13 ECU. This seems to tell the ECU when to turn on the compressor and fan, subject to other conditions (such as whether you are driving WOT). The ECU then sends a signal out pins 43 and 47 to switch on the relays for the compressor and fan. But since I won’t be running the S13 ECU (or ANY ECU with controls for the A/C system), how should I trigger these relays? Should I just connect the A/C amplifier output to the relays? Or do I need something else, like perhaps another relay to control these relays?