LBZ Intermittent No Crank

[JDT4430]

Well lets see if I can explain enough to get some good help. A friend of mine has a 2007 LBZ that has an intermittent no crank as in wont turn over dont click nothing. Dash lights come on head lights come on will not crank amd the blowers do not come on. We have checked fuses, relays and have put new batteries in the truck and put a new starter relay in the truck. The first day it happened he had been driving it all day and started several times with no issues then he went home to get something and shut off for about ten minutes. When he came out it would not start. Thats when we checked all of telhe items mentioned above and the next day he put two brand new batteries in the truck with no luck. As I read through issues on here it started to sound like the TCM so I called him and told him to swap it out woth there other truck but he said he walked out and tried to start it and it started fine. He then got the TCM out of the other truck and continue to drive his for a few days before it messed up again. He then swapped out the TCM with no luck. He then let it sit for a few days agian and ut eventually cranked up and ran fine for several days again. This has been going on for a few weeks now and yesterday he tells me while he was driving down the turn row of one of their fields all the lights on the dash came on and the blowers shut off and he figured it was going to die but it didnt so he continue to drive it to were they park and before he got there the dash lights went out and the blowers came back on. I have pulled codes U0101 Lost Com With TCM, U1026, & U1064. He also said the service 4 wheel drive displayed on the dic one day. He also took the TCM from his truck one day when it wouldnt crank and put it in there other truck and it started with no issues so that pretty much eliminates the TCM. Any help is appreciated.

 

[Robby Avery]

Start by checking the two big bale connectors I can't recall the circuit numbers. unplug them and replug them back in see if that's the culprit. they can have pitting or fretting on the terminals that cause a intermittent problem try applying die electric grease. a light coat is suffice use a clean q tip and apply to the male terminals on both large connectors. they are located on the top right side of the engine near the right side of the turbo directly over the coolant tube leading back to the thermostat housing. Also check fuses if none are blown disconnect batteries and remove the underwood fuse block and check the terminals there for any signs of arcing or corrosion inspect throughly. Next would be to start supecting the the inline harnesses to the trans or engine for chafing or rodent damage could be a loose ground or the main connector at the back right side of the trans these are some places to start. Let us know what you find so we can better assist you

 

[JDT4430]

Ok I will pass this info on to him. It may be a few days before he gets a chance to check it out since they are in full blown corn planting mode right now but either him or I will investigate these items and report back. Thanks

 

[DMAXDFloridian]

Did this issue ever get fixed so anyone else with this issue may learn.

 

[JDT4430]

OK its been a very busy summer and we have looked over all the wiring and checked connections best we could and still have found nothing. His boss said the hell with it and was going to get him another truck and that has been going on for several months so he decided to change the steering column because the shifter mechanism was jacked up and thought that maybe it was the ignition switch but that did not help either (when did a relearn on the key). We also tried another ECM to find out that evidently you can not just swap computers.

I read somewhere that if you swap the ECM and TCM from one truck to another they will work. Is this true or not. We have access to another 07 classic LBZ but want to make sure this will work before we go pulling parts from one to another.

I appreciate yalls help and I apologize for the long delay but they had a spare truck he was driving and now they hired someone else so we need to get this one going again.

Also he said it will start and drive if he jumps the starter solenoid but he has all the lights on, on the dash and the blowers will not work.