Does the blower and a/c switch need to stay on to while the engine is running, or can it be shut off afterwards? For this, I assume the latter?

Are you simply extending the main relay ground to the ground at the a/c switch, or are you running two wires from the main relay harness to go to the switch, and then back to the relay?

 

yeah this!

 

AC and Cruise control cutoff switches!

 

No and no.

The A/C switch is just used to latch a latching relay, once the relay is latched it stays latched until the ign. is turned off, the latching relay is where the "cut" is connected to, if it is used on the PGM-FI Main Relay ground then the PGM-FI Main Relay ground is run through the latching relay.

If the latching relay is not used, then the A/C switch and the blower would need to be on as long as engine is running.

A simpler system could be used, rewire the ground input to the A/C switch from the blower speed control to direct ground, then connect the output of the A/C switch to the PGM-FI Main Relay so the switch supplies the ground, or rewire it buy running the PGB-FI Main Relays ground through the A/C switch, in either of the above the A/C switch would have to stay on. 94

 

Holy crap, that's a lot to take in. Looks like I need to start researching some more about these latching relays.

 

A latching relay can easily be made with two (2) standard automotive SPDT relays. 94

 

this sounds like what I want to do, and i obviously have to keep the A/C button pushed in, in order to have the car running, which I dont mind. but I dont have the blower for the A/C, so I Have to do the latching relay?

 

If your not using a latching relay, then yes, you would need to keep the switch pushed in. 94