42RLE automatic transmission slipping intermittently

[sprowls]

My 2004 Jeep LJ started revving while driving like the transmission disengaged for a few seconds. The Check engine light also turned on. I had the jeep towed home and then began to investigate. It did not go into limp mode and seemed to drive okay after being towed home around the neighborhood. I pulled the following codes with my blue driver scanner

After some research on the forum I decided to change and flush my transmission fluid and filter. The fluid was not burnt but it was filthy. I then drove around for about 20 minutes and it did rev on my one time in the first few minutes of driving, but after some more driving the CEL cleared as well as some of the other codes. Getting the codes from the odometer only gave a P0700. The scanner then pulled the following codes

I then cleared the codes with my scanner, replaced the battery as it was 4 years old but was showing 12.54 volts, and touched the negative and positive battery cables to clear the codes. I drove around for another 30 minutes or so on the highway and the odometer does not give any codes and my scanner gives the following

I have been talking to Mark @Wranglerfix and have a new TCM on order, but now I'm starting to think my PCM may also need replacing due to the Side-Impact Airbag Control Module codes. Has anyone seen these before?

I'm still in the process of tracing my wiring harness looking for shorts. Is there a smart way to go about this or is it a full end to end check unwrapping everything?

Some possibly related threads
https://wranglertjforum.com/threads/code-p0562-low-voltage-tranny-shifting-issues.6834/
https://wranglertjforum.com/threads/42rle-automatic-transmission-slipping.62810/

 

[LONGJP2]

My 2004 Jeep LJ started revving while driving like the transmission disengaged for a few seconds. The Check engine light also turned on. I had the jeep towed home and then began to investigate. It did not go into limp mode and seemed to drive okay after being towed home around the neighborhood. I pulled the following codes with my blue driver scanner

View attachment 532191
After some research on the forum I decided to change and flush my transmission fluid and filter. The fluid was not burnt but it was filthy. I then drove around for about 20 minutes and it did rev on my one time in the first few minutes of driving, but after some more driving the CEL cleared as well as some of the other codes. Getting the codes from the odometer only gave a P0700. The scanner then pulled the following codes

View attachment 532193

I then cleared the codes with my scanner, replaced the battery as it was 4 years old but was showing 12.54 volts, and touched the negative and positive battery cables to clear the codes. I drove around for another 30 minutes or so on the highway and the odometer does not give any codes and my scanner gives the following


View attachment 532194
I have been talking to Mark @Wranglerfix and have a new TCM on order, but now I'm starting to think my PCM may also need replacing due to the Side-Impact Airbag Control Module codes. Has anyone seen these before?

I'm still in the process of tracing my wiring harness looking for shorts. Is there a smart way to go about this or is it a full end to end check unwrapping everything?

Some possibly related threads
https://wranglertjforum.com/threads/code-p0562-low-voltage-tranny-shifting-issues.6834/
https://wranglertjforum.com/threads/42rle-automatic-transmission-slipping.62810/

Slipping / revving sounds like the torque converter.

 

[sprowls]

Cleaned the ground wires although none looked bad, cleared to codes, and went for a 30 mile drive and no new codes. Knock on wood the transmissions seems better than it has for the last couple of years. I was planning to take it on a week long trip starting this weekend, but I'm not sure what to think. I'm going to put another 100 miles on it and see if any codes re-appear or any more revving.

 

[Cooper Smith]

Cleaned the ground wires although none looked bad, cleared to codes, and went for a 30 mile drive and no new codes. Knock on wood the transmissions seems better than it has for the last couple of years. I was planning to take it on a week long trip starting this weekend, but I'm not sure what to think. I'm going to put another 100 miles on it and see if any codes re-appear or any more revving.

Don't the TJ's have a dedicated airbag control module?

 

[sprowls]

I'm not sure if there is a dedicated airbag module, but I know there are no side airbags on a TJ/LJ.

 

[LONGJP2]

I'm going to put another 100 miles on it and see if any codes re-appear or any more revving.

Make sure to test it on some long (interstate) inclines. That's what seems to get mine heated up.

 

[sprowls]

Update: I drove the jeep about 2500 miles round trip to Steamboat CO and back with a stop in Moab and did the Poison Spider trail with no transmission issues and no codes. I'm still a little worried about the side airbag code, but I'm assuming the new battery and cleaning the grounds took care of that. Unless something else comes up, I'm going to consider it resolved for now.

 

[TexasTJ2004]

In 2003 and 2004 42RLE has a separate transmission controller, this is why I don’t think that WranglerFix can help you here. AFAIK he addresses the problem that is specific for 2005-2006 in TJ, where the PCM controls 42RLE as well.

 

[sprowls]

on 7/17/24 jeep went into limp mode and check engine light with the following codes

• Trouble Codes
  • P1776 solenoid switch valve latched in LR positions
• Audio System Component - Amplifier Codes
  • internal failure
  • 73 inoperative watchdog inhibit
  • 72 ROM incident
  • 71 RAM incident

They cleared themselves and and not trouble in the last month, monitoring to see if it was possible dirt/gunk in system or a bigger issue.

 

[AndyG]

Following.

If the harness is ok I’d sure be talking to Mark and also get a it on a good laptop while driving and see if the converter is locking up when it should.

The 42 self destructs from a poorly calculated overdrive and the excessive heat it creates.

The scattered codes do make me think pcm/tcm/electrical may be the issue.

I just had to have mine rebuilt, and it had less than 58,000 miles.

Incidentally the 42 is so smart it will even tell a computer when the new torque converter is broken in.

 

[TexasTJ2004]

on 7/17/24 jeep went into limp mode and check engine light with the following codes

• Trouble Codes
  • P1776 solenoid switch valve latched in LR positions
• Audio System Component - Amplifier Codes
  • internal failure
  • 73 inoperative watchdog inhibit
  • 72 ROM incident
  • 71 RAM incident

They cleared themselves and and not trouble in the last month, monitoring to see if it was possible dirt/gunk in system or a bigger issue.

You need to replace the solenoid pack.
You need to drop the transmission oil pan, then the valve body and install new solenoid pack. Brand new is 300$ reman is like 120$.
Replace the filter while you at it.
I did that, transmission stays in the jeep, no need to remove the transfer case skid.

 

[TexasTJ2004]

Looking into the history of the thread: did you check that all the contacts are good?