I just checked the schematics for the fuel pump relay. The 12V going to the relay for the fuel pump power is HOT ALL THE TIME! The 12V going to the fuel pump relay coil is HOT during RUN and START. You can also pick this 12V up going to the coilpack (red/green wire).

 

Ok, I'll check that in my wiring diagram to find where the easiest place to pick that up will be.

 

Is it done yet?

 

Nope, finishing editing a few how-tos and then I'll go outside and do work.

 

So use the ground side which would be grounded for start/run to trigger a relay for the radio....

You don't have to use power to trigger a relay you install. Just my 2cents

 

If he uses a 12V circuit that is HOT during RUN and START, he won't need the additional relay. The only problem with this, his head unit will not work in ACC mode.

 

He has to make sure he disconnects the factory wiring to the radio too, or his fuel pump would run in the acc mode.

 

Yeah I wouldn't use both wires together. I'm going to work on power to accessory when the key is out then I'll try both of these.

 

Yes, he does need to disconnect the present "switvched 12V", but if he didn't, the fuel pump wouldn't run in ACC mode, because the PCM wouldn't ground the coil on the fuel pump relay.