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no bus and no start/crank


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Story goes, I parked the truck, pulled the motor to build up a little bit and when the truck was parked everything ran and worked fine. Truck is a 2002 p-pumped 24v, 4x4, six speed. I finally got to put the motor back in, was out about a year d/t a deployment. turn the key and nothing, no cranking or click or anything. Swapped all the relays out to determine if it was the starter relay, still nothing. I ran a jumper wire from the where the relay would create a hot terminal with the "start" position and the truck fires over and runs fine. I'm obviously getting power from the ignition switch to the relay and the junction block, etc. I'm assuming that the "no bus" condition is causing this no crank issue as well. the lift pump will not run either, making me think the ECM went bad. Also, I've by-passed the clutch safety switch to rule that out as being faulty out as well. the only thing that was changed from parking the truck until now has been mechanical things and i took out the second battery for room for the twins. I've gone through every ground wire i can find and have sanded the contact point and added some dielectric grease to all connections.

I've disconnected the PCM, the entire engine wiring harness, the overhead console, the airbag module, the anti-lock brake module, the radio, swapped the gauge/instrument cluster, disconnected the large plug under the fuse block under the hood that is bolted in, and i've disconnected what i think is the harness for the central timer control (under the dash on the left side by the main bolted wiring harness), all items that are run by the BUS system from my VERY basic understanding from reading on here, looking at the wiring diagrams and having a short converstation with Mr. Nelson. I've been checking the voltage at the OBDII port and haven't been able to achieve the correct voltage and I think I've come to a dead end. The voltages are close, pin 3 is 2.47v and pin 11 is 2.45v or 2.46v.

I'm at my wits end here guys, please help me out. My cell is 301-455-one9one8 if you want to call and try to talk me through anything i would greatly appreciate any help at this point.

Thanks

James

- - - Updated - - -

update, the grounds from the passenger's side battery were not connected properly, got them grounded and she starts and runs like a champ.

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