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Discussion Starter · #1 ·
Ok guys.... Not sure what happened in 5 minutes of the truck on its own, but it will not turn over. Drove to town and back. Shut down. Tried to fire up say 5-10 minutes later... Nothing. All lights are working, and no blown fuses that I see. Tried disconnecting batteries to reset, did not help. My brake light is staying on, flashing service 4wd, and have 2 codes: U101(TCM connection/miscommunication) and P0504(brake switch?). I then cleared these codes, attempted to start, and still nothing. U101 came back, P0504 did not, however my brake light is still staying on(which maybe it always does until you start) but i don't belive so. Low on sleep, so Ive got partial use at the moment lol Bear with me. Am I missing something or did the tcm up and grenade when I walked away?


Any help is greatly appreciated! I haul regularly throughout the week, so I need the truck up and going again asap!

Thanks in advance! I will be searching now as well, but wanted a thread up for immediate help if at all possible.
 

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Discussion Starter · #2 ·
I do have continuity between 9 and 69. From what I read, this means the tcm is ok? So what am I missing?
 

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Discussion Starter · #3 ·
Anyone?
 

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Remove the start relay from the hood fuse block for 12 volt when you turn the key to "Start"- then jump the 12 volt terminal to the relay starter terminal. Does it turn over-?

My first "Guess" would be batteries-- with any "No-Start" condition, it is always advisable to have the batteries tested first-- be sure you isolate the one being tested. That will eliminate that as a possible problem.
 

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Discussion Starter · #5 ·
Batteries are new, but also tested. They are good. And yes, it turns over when I jump the relay
 

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Discussion Starter · #6 · (Edited)
I also tried to ground the tcm casing to the ground near the B+ terminal. This did not allow it to start. Meaning the tcm internal ground is fine? Truck will not shift into gear without applying the brake, so ign switch is good. Again, batteries are good, and all fuses seem to be good.
 

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Discussion Starter · #7 · (Edited)
Well, actually did end up being a fuse. Green 40amp block under the hood... Guess I didn't notice last night. Problem solved.

Thread can be removed from 911. Thanks
 
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