Howdy.

First time long time.

Got a 96 XJ 4.0 with an AW4

It's starting in 3rd when I put in in drive. When I shift down to 1st it runs fine.

Some context: I was replacing the front wiper fluid motor but found out that it wasn't getting power. Instead of ordering a new one I just swapped hoses with the back one and we're in business.

Before I resorted to that I wanted to check the length of the motor's wire to make sure it wasn't damaged. I had been meaning to re-tape my wiring under the hood for a while, so I took the opportunity and cut off the old tape. Didn't find any damage. Removed the lower dash to check the wire as it entered the steering wheel. No damage.

In the process, I disconnected my TCM in order to get the dash out.

After rigging the washer pump I went to pull in to the garage and it started in third. Realized that I forgot to plug the TCM back in. Did that, still started in third.

At this point I've

• Checked for codes, nothing
• Checked the fluid level
• Checked wiring under hood for damage that may have occurred when I cut the tape, didn't see anything
• Replaced TPS. Tried two different ones to eliminate the possibility of a dud.
• Connectors at the transmission look clean and intact. Same with the ones under the hood.
• Tried a refurbished TCM from a reputable ebay seller
• Checked solenoid resistance with the TCM plug, solenoid 1 was a bit high at 18Ω
• Replaced all shift solenoids

I keep going back to disconnecting the TCM when I was inspecting the fluid pump wiring. Thats the only thing it could be in my opinion, nothing else changed from before except rerouting wiper fluid. Everything I've seen indicates that you don't need to reset or program anything after plugging the TCM back in. I drained the capacitors just to be sure. Didn't help.

One weird thing: my TCM doesn't have an in line 10a fuse, just runs straight into the firewall.

Any help would be appreciated.

 

Pull the battery terminals, touch them together and put them back. See if it resets

 

Tried that, still starts in third.

I think I might try a brand new TCM next, but that's $$$

 

I would try to test continuity between the TCM and solenoid that controls Gears 1 & 2

Its possible this has been disturbed by disconnecting the TCM

a few tests

* measure resistance between (unplugged) TCM plug pin to solenoid pin on engine bay plug (key off)

* insert pin backprobe in engine bay cavity ( or pin backprobe close as possible to plugged in TCM solenoid No1 output.

This should show 12V or a test light if the TCM is sending the signal

It may be you have "broken" the internal pin to circuit board connection on the TCM, I believe they can be soldered

used TCM are available

 

Only the older Renix era XJs had the inline 10-amp fuse. You're most likely starting in 4th, meaning the TCM has no power or the #1 solenoid is bad. It's pretty rare to have a bad TCM. It's time to break out the meter and again.

D16 - Fused Ignition Power (Yellow) Fuse 21, 10-amp
D14 - Fused B+ Power (Red) Fuse 6, 30-amp
C14 - Torque Converter Solenoid (White/Black)
C15 - Solenoid #2 (Violet/Black)
C16 - Solenoid #1 (Dark Blue/Black)

Both D16 and D14 should have power with the key-on.
C14-C16 solenoids should measure 11-16 ish for resistance.
C16 should have power and C14/15 no power from the TCM to command first gear.

 

Well I'll be damned, I checked fuse 21 a couple weeks ago but completely missed this. Jumped it with a paperclip and she runs like a charm. Funny enough I bought this box off of ebay because an AC relay cavity was busted on the old one, but it's been months since I installed it and I hadn't had any issues. Must have broken when I was checking fuses recently.

Appreciate the help guys.