I've looked around but can't seem to find anything with answers I'm looking for. What I'm going to is wire a momentary toggle switch to power the toaster relays to switch them on. I did this a few years ago on an old ford I idi I had and it works great.. My question is how many amps should the toggle have going through it to power both the relays on at one time..or should they work independent of each other? I'd also pretty soon like to wire a momentary toggle for the lift pump prime.. To where the computer would run it once the truck was running..but where I could hit a switch for a second or two right before start up to prime it. Sometimes I have issues with the computer kicking it on with ignition so it won't start.. Sorry for the long *** write up. Thanks in advance

 

What year truck we dealing with?

You won't need much of a switch, and I would put 2 so you can toggle them independently.

You will be using the switch to bring in the relays that power the grid heaters.

As for your lift pump, I will let someone else answer that, I would think it should be very similar as the PCM controls it, probably just dragging a solenoid to ground.

 

Good info on the GH circuits........

Ram Diesel Manifold Heater Problems

 

My truck is a 99.. Thanks for the info..so for each switch I have to fuse the power to the switch before it hits the relay..so what a ten amp fuse on each switch.. Or less?