Tricky No Start Electrical Issue

[Brandon Kownirk Donovan]

Hello, new here, and I need help troubleshooting a truck I just bought. The engine, starter, fuel pump, and transfer case I know are good. Though, what I think the issue is a bad ground, a bad park sensor, a result of cut wires within the dash, or a bad ignition switch.

 

Here is what I have observed:

- No gear selector underline on the dash to let me know what gear I am in

- No security issue

- I cannot scan using the OBDII port

- There are 5 wires hanging down, cut, coming from all the way up from what looks like a junction box with a bunch of connections

- No clicks, no fuel pump, no turnover upon trying to start the truck.

 

What I currently assume is that because the truck does not know what gear it is in, whether Park or Neutral, it does not want to start. Now I am wondering, what does it take for the truck to want to start? The previous owner seems to not know what he is doing and tried to cut random wires, try silly fixes, and he took apart the lower dash and steering column covers. I do not know what has gone through his head, and the reasoning he gave me does not make sense.

 

Any help or advice is appreciated, and I hope to learn a lot as I fix this issue!

 

Edit: It is a 2007 Extended Cab Sierra Worktruck WT trim, no power windows, locks, ABS, etc.

Edited August 8, 2021 by Brandon Kownirk Donovan
Additional information

[Sharpz]

sounds like you should just go to a pull a part and get your another harness. Save yourself grief. Whilst there pick up another BCM, and if you have the money another PCM.  If this person randomly started cutting wires, it might be because they had the same issues, or the security theft system was preventing them from starting it and they thought cutting certain wires would bypass it.

I will say cutting wires is different in removing something like a security alarm, brake system, or remote start.  If you remove something  you will only see the wires cut with no apparent place for them to go.  Cutting harness wires would still leave two ends unless the person traced them down and pulled them out for whatever reason.  Inspect your area real good for tucked wires, before proceeding. 

[Brandon Kownirk Donovan]

Thanks for narrowing it down a bit. I have found that the RUN/CRNK relay works, as I pop it in and out there is a click in the intake.

Unfortunately that does seem the route to go. What I will do is spend a good day pulling the entire wire mess down and see where the wires came from. I'll print off a bunch of wire diagrams, and hopefully see what happens when everything is all plugged back in. If I am desperate, I'll try cleaning grounds all over, checking for voltage in the fuel pump, starter, etc.