For about a month i have been getting code U0101. It happens randomly. When its there the truck will crank but wont start. I can clear the code and it fires right up. Its never shifted funny or anything. I read somewhere that its been found to be the electronic module that the key switch(tumbler) activates. I bought and installed a new one. Now the code is there and i cant clear it. Engine cranks fine but wont start. Do you guys have any ideas?
I need help!!
- Thread starter Cda55
- Start date
Look at the position of the detents in your old switch and move the detents in the new switch to the same position. Re install.
I have spent about 3 hours and havent been able to clear the code. Ive moved the little gear one tooth at a time. Is it possible my tcm has quit? Any way of checking it? If i had one from another truck can i swap it out? Does it have to be same year, tranny, and engine?
Its a 2006. Update on it. This morning i checked the tcm harness again for any bad spots. I found none. I hooked it back up and checked for power at the ignition module with the key in run. With the switch out i moved it to start position and the truck started. I let batteries charge for a bit. When i shut it off and restarted it stumbled and idled very low. Scanned it and had the U0101 again. Dumped it and it runs fine now. Since i think it has to do with the tcm i figured id use my ppe standard to reset the transmission is hopes of it clearing up the U0101 issue. It wont reset the transmission now. I pulled the electrical plug from the passenger side rear of tranny and it has fluid in the plug. Not a lot but its there. Can that cause this issue? Do i need a new harness in the pan? Or is it still a tcm issue? One of the guys mentioned a tech2. I dont have one nor do i know anyone with one. I looked online and some are 300 bucks and some are 5 grand. Will the 300 one do what needs to be done? If so i dont mind buying it. The 5 grand is a little bit much! Can a dealership scan it and see what the problem is? Or if the 300 model will do the same i will buy it and skip dealership. Thanks for all your help. I needed it! I live in a little town in central cal and resources here are limited.
Latest update. After messing with it most of Sunday it cleared the code and let me reset the tranny. It shifts fine and runs fine. It doesnt allow me to use the manuel shift mode. And the batteries are only getting 12.7 volts. The display says batteries not charging. I think my problem may be in the ground on the passenger side of the engine. Is there anything else that would affect it the way it is? I want to make sure im not missing something.
I know low voltage does funny things to a car. Especially these trucks. I had my doors randomly locking and unlocking. Interior lights coming on and going off. Checked and had good voltage at the battery but were barely holding a charge. Come to find out of was a dead cell in both. Replaced them and all the random issues stopped.
When I first purchased my truck I took it to shop I had known for a number of number of years to exchange the transmission fluid. First thing he said when I told him year make and diesel, keep an eye on the batteries, they can do some F****D up things when they start to go out....
Second course of action after the fluid, new batteries as it still had the 2006 OEM's in 2013 when I purchased it and the passenger barely passed a carbon pile test, may want to have the batteries tested..
Second course of action after the fluid, new batteries as it still had the 2006 OEM's in 2013 when I purchased it and the passenger barely passed a carbon pile test, may want to have the batteries tested..
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