Code U0101, will not start

When you try to start the engine, does the starter engage or does nothing happen? The code you have indicated a breakdown in communication between the PCM and TCM.

If you look at pic 1 below, it shows possible causes.

Pics 2-5 are of the TCM wiring. I highlighted CAN wiring and fuses I would like you to check. Also, I need to know if the starter is engaging. The next two pics show fuse locations. The last picture shows the wiring systems that could be related to the transmission. I need you to see if when the key is in the run position if the gear indicator is correct. It could be wiring from the range sensor which is indicated in the last pic.

The wiring schematic was two pages. However, I had to cut them in half to make them readable for you. I overlapped them so you can follow from one to the next.

Let me know what you find or if you have other questions.

Joe

See pics below.

Hi,

It sounds like you have your hands full. I'll try my best to help. Also, you are always welcome on this site. We will always try to help.

Since the starter doesn't work, let's start at the beginning. First, I attached the starting system schematic below. I cut it in half but overlapped it so you can follow from one to the next.

In the fusible link box (near the battery), locate fusible link J. See pic 3. I need to confirm power to and from it. If you look at the wiring schematic, not it powers the ignition switch. From there power goes through fuses and relays (tied into the CAN). Check those fuses as well.

If that is all good, I need you to confirm if the shift indicator is working indicating what gear the vehicle is in. For example, P, R, N, D.

If that is working, I need you to go to the starter. You will need a helper for this. On the starter, there will be a larger wire straight from the battery which should have 12v at all times. There will be a smaller wire which is white. The white wire should only receive 12v when the key is in the start position. Have your helper turn the key to the start position while you check for power at the white wire. Here is a link that may help you:

https://www.2carpros.com/articles/starter-not-working-repair

Also, let me know where you hear the click noise. Is it from the starter or the relay/fuse box? One last thing. Carefully confirm power on the larger wire to the starter. It should be black/red in color. Remember, that is hot at all times, so don't short it. You can use a test light for checking.

Let me know.

Joe

See pics below.

Hi,

You are very welcome. I will try to help from my end as well. By jumping the starter like that, you confirmed the starter is good. By checking the white wire, you determine there is a break down between the starter and the electrical system.

Since the code is related to the TCM, did you check to see if the gear indicator is working? Have you tried to see if it will start in neutral?

Let me know.

Joe

Hi,

First, let me know which fuses were replaced with a wire. That is very dangerous. It can lead to a fire. We need to get the correct amperage fuse in there.

If you have no gear indication lights, something is happening with the transmission range sensor.

I attached pics of the three fuses I'm most concerned with. Pic 2 shows the location in the box. Please make sure they are good. Also, make sure there is power to and from them. If these are ones with a wire placed in them and not a fuse, there is a chance the transmission control module was damaged.

Let me know what you find or if you have other questions.

Take care,

Joe

See pics below.

Hi,

The fuse box above should be the one in the glove box. Also, do you mean that only one side of the terminal on the fuse has the wire? We don't want the wire to jump from terminal to terminal.

I have all the power distribution schematics, but I don't think that's what you are asking for. Let me know.

Joe

Hi,

I'm glad to hear you got it running. As far as the power loss to specific fuses, chances are there is an upstream fuse that is bad. If that isn't the case, then there has to be an open circuit at some point or something preventing the flow of power.

I attached the entire power distribution schematics below. I cut them in half so you can read them, but I overlapped them so you can follow from one to the next.

Locate the fuse you are having trouble with and then follow the wiring back to locate where it originates. If you have trouble or questions, let me know.

Here is a link you may find helpful:

https://www.2carpros.com/articles/how-to-check-wiring

Let me know.

Take care,
Joe

See pics below.