Will not crank unless bypass relay

[jedwilli]

I have a 2003 H2 that will not start unless I use a jumper wire on the relay to manually engage the solenoid. I've checked the wiring, the neutral switch, the ignition switch, etc. I'm at a loss.

Any ideas to help me troubleshoot this?

-jw

[jedwilli]

I replaced the ignition switch - still no joy. To be clear, a hot wire to the solenoid and it fires right up. Proves starter and solenoid are fine. I've checked the neutral switch as well - it appears to be working. Any ideas I would appreciate it.

-jw

[jedwilli]

I also traced the wire from the solenoid to the fuse box and can use a jumper at the fuse box. It starts at that time. Checked all the fuses multiple times. Could it be the main computer?

[jedwilli]

:confused: Anyone have a suggestion?

[Planohummer]

look under the dash, around steering column to see if anyone has removed either an alarm or a remote start system. ck purple and orange wires specifically.

[jedwilli]

Nothing that I can tell. I've had this thing for a couple of years - it worked great until last week when I backed it into the driveway - then this behavoir started. Can you or anyone give me a wiring schematic for the igntion circuit. It seems like something has been cut or something. I did take the fuse box cover off (under the hood) and I had a nice little mouse nest - but I do not see any chewed wires. I'm at a loss.

-jw

[Planohummer]

take the fuse box off and look at underside-there's plenty of nesting material for them to harvest.

[jedwilli]

Ii did take the fuse box off and there were a few wires with the insulation chewed... none of the wires were broken though. I repaired the insulation (electrical tape) but still same issue. No blown fuses though. I've swapped the relays and the ignition switch. Any additional ideas? I'm at a loss.

Truck runs fine when I start it using my jumper wire - makes me think computer is fine. I'm running out of ideas.

-jw

[Planohummer]

ck ign 1,2,3 fuses. they're the wierd looking ones in the middle of fuse block.

[Marcmedic]

My 04 did the same thing. Some sort of switch that didn't recognize the vehicle was in park. It thought it was in gear and wouldn't allow the truck to start. And another time my starter had a "dead spot" as the dealer put it.

[jedwilli]

I've checked the ignition fuses - the 40amp wierd looking ones - they all seem fine. Any ideas how to check neutral switch? I took it apart and it looks fine - but I'm not sure how to tell for sure.

[jedwilli]

I replaced the neutral switch today.... still no joy. Any additional ideas from anyone? I'm runnning out of things to replace.

Help please!