New to the forum. This is my first dmax. I have a dead dmax no crank/no start. Serivce Brake System is on the DIC. No codes. Checked fuses and swapped the ecm relay and tried grounding the TCM but still won't crank. Batteries are two months old and have 12.5 volts. Any ideas?
LBZ: No Crank/No Start
- Thread starter dmax604
- Start date
Dumb question but is it showing its in park? Maybe try shifting to neutral and trying to start it? I'm not familiar with the neutral safety switch on the Allison but maybe the truck thinks its in gear or something.
Sint frum tha orijinul smert fone
Sint frum tha orijinul smert fone
My first recomendation is to check +voltage at starter solenoid. Then with an assistant check voltage at the ignition terminal on the starter for voltage while your assistant turns the key to crank.
Check the main harness coming out of the under hood fuse box and make sure it hasn't rubbed through on the inner fender liner. Don't ask me why I know this to be an issue with some LBZs...
Wierd thing is two weeks ago my truck shutdown two times while driving. Still had full electrical power just the engine died. Fired right back up both times. Engine light came on brought it home and shut it off, after that no start/no crank. My buddy brought over his scanner to get the code, his scanner couldn't communicate with the engine, but the truck fired up. Ran to an auto parts store grabbed a cheap scanner, code was the ecm relay. Cleared code, truck ran no problem for two weeks. Then out of nowhere no start/no crank and no codes. Also swapped relays under the hood with no success. Why would the ecm relay code come up if the relay appears ok. Thanks for all the input so far guys! This is frustrating!
This past summer my truck did the same thing. I drove it the night before and the next morning all the dash lights came on but wouldn't start. The starter was locked up and i had to replace it.
This is what I found so far. Checking voltage at the under hood fuse box I have 12v at IGN E 10A, ECM 1 15A, and the ECM relay. I loose voltatage only .7V at ECM 25A, and Actuator 15A. All voltages were checked while trying to crank. I have no voltage at the signal wire on the stater while cranking. I moved a bundle of wires away from the inner fender well and notice a wire that has the sheathing melted/worn away and most of the wire. The wire comes from the lower connector of the ecm. It's gray and has a black stripe. Didn't notice any other damaged wires. Could this one wire be the problem? Thanks!
I had no click, no crank, no start. Took me days to find that friggin' rub through. (there is a thread on DP that I think I titled "It's Dead Jim" if you wanted to go look for more info)
Thought for a minute about splicing it myself, but the truck was less than a year old, so I had it done by the dealer. Only warranty work I have ever had done and only time my truck has ever been on the hook....:thumb:
According to the paperwork, they did the GM proscribed splice to repair it. The GM method uses crimps and wrap. Frankly I am not sure soldering would be better in this case as it makes a brittle joint. Good crimps and good heat shrink might be better.
Pop the fender liner, open up the loom to get at the offending wire and put a fresh piece in (even as a jumper) to see if it solves the problem and then make it permanent if that does it.
Final update! I put a butt connector in on the rub through wire and she stars! I am going to do a more permanent fix with shrink wrap and tie the wires away from the fender well, if possible. It took five days but I can finally drive my truck again! Thanks to all the posts for the useful info!:thumb:
I am going to do a more permanent fix with shrink wrap and tie the wires away from the fender well, if possible. It took five days but I can finally drive my truck again! Thanks to all the posts for the useful info!:thumb: