2004 4300 No Crank

[bgblk1968]

Truck came to me with a mess of problems mainly no crank. I rewired fuses in battery box. I traced the main battery feeds and found one wire that was almost corroded in two. Repaired those and replaced a majority of the relay terminals in power distribution box as they were corroded. Everything appears to be decent, but it will not crank with key. Starer relay is receiving 12 volts from ignition switch. ECM is not sending out ground to relay. Would that short I found smoked the ecm? If I bypass starter relay, it cranks and runs good. Cleaned grounds and positive terminals. Also something that is acting up is wipers act like they have a mind of their own. May come on randomly. i was positive I found issue when i found that wire. Truck has an allison and it is recognizing park/reverse/etc. I'm stumped.

[Diverdude0075]

Try replacing the CPS? Then again, I guess it wouldn’t run if it were the cps. Cheap to buy though and try plus it’s good to have a spare.

[ewo1]

Try pulling codes. If the ECM responds it might just not be toasted.

When you turn the key switch to the ON position, do the dash gauges “sweep”?

That is your Ecm post test indicator; that at least the ECM is trying to do it’s job.

Also you didn’ mention what engine your working with.
Did you check the ECM fuse?

[bgblk1968]

Dash does sweep and laptop see ecm. No codes. It runs fine when I jump starter solenoid. What tells the ecm to send ground signal to starter relay? I assume neutral safety switch, but is there anything else?


Oh, its a dt466E