Help!! DTC P0603

[027.3]

Truck won't run and this is the DTC P0603. I looked it up but don't understand what it is or how to fix.....just a sensor I hope. Thanks

[NoRalPh]

Nothing to worry about, P0603 says your batteries have been disconnected recently.

Not Starting isn't part of it UNLESS it won't even "crank" then it's telling you your PCMs, "keep alive" memory has been erased because of a Total Loss of power to it.

[027.3]

I changed batteries a few months ago so maybe its from then. What its doing now is when I start it it , let me see if I can explain, it runs like I'm taking my foot and mashing the gas and then lift, then mash, then lift and so on, but not reving it up, just mashing and lifting quickly, almost like i'm holding the pedal down and turning the ignition on and off real fast. If I touch the pedal while its doing this it smooths out and idles normal. I don't know if that makes any sense....I'm going to make a video in the morning so I can show what its doing.

[NCHornet]

I already replied to the same question you posted in the 7.3 section. I would check your GP system, that is where your problem is, time to do some work. Takes 30 min to do the entire system.

NCH