Here is one for the Sherlock Holmes out there...I've been having problems with the auto trans of my '05 Montero Ltd. (US). At startup, when cold, it was taking long for 1st gear or reverse to engage, I tried 2nd gear using the Sportronic mode and same thing, it got solved by changing the trans fluid. Every now and then, when cold, it still fails to properly engage, but only for 2-3 seconds, so it is not a big issue for me. When trans is up to operating temp it works flawlessly.

This morning when I started the vehicle it didn't engage 1st at all, though reverse engaged without a problem, so I accelerated and noticed the trans slipping, then engaging, then slipping, then engaging, and after about 1/4 mile the vehicle would not move, you could feel the trans trying to engage gears. Then, the gear indicator in the dash panel lit up the Neutral position, and at the same time it lit up 3rd gear (blinking); the Service Engine Soon indicator also lit up. So, both lights were lit up, N and 3, N was solid and 3 was blinking, plus the Service Engine light. I changed the trans to reverse and it worked perfectly, changed it back to drive and the above mentioned problems started again. This all happened in a time span of about 5 minutes.

Anyways, by this time I figured out that the problem has to be electronic, so turned the vehicle off and waited about 10 seconds to see if the ECM would reset. Started the vehicle, put in D (drive) and it immediately engaged 1st and I went on my way. Took it to my mechanic and we hooked up the OBDII diagnostics, and it gave us the code "P0735", but that could be many things. The weird thing is that code P0735 is for 5th gear, and the vehicle never went into 5th gear. I asked him to reset the Service light and see if it would do it again. That was this morning and so far it has been working fine. But, I'm sure it will happen again, the question is when and where.

My best educated guess is that the problem is the solenoids, other threads or forums talk about the "Freewheel Clutch Valve", but I believe this only applies to 4H/4Hc/4Lc as it has to do with the front diff, though I might be incorrect on my assumption.

Has anyone had a similar problem? What was the solution? I don't want to spend $1K+ dollars on a trans shop saying it was the trans, when an inexpensive solenoid change might do. My mechanic is extremely reliable and honest, but he doesn't work on trans and he doesn't recommend trans shops, because he doesn't know any honest ones.

 

Today, same thing, it seized, N lit up, D flashed, turned on-off the vehicle. It reset and went on it's merry way.

 

Update! New Code: P0734 (same as P0735, but for 4th gear) Checked the OBDII computer and All Data, it can be any of a variety of sensors, but the most common ones is the Input Speed Shaft Sensor and/or the Output Speed Shaft Sensor. Will have to check voltage to see which one is failing.

When there is a difference in speed from 1st to any of the other gears the vehicle goes into fail-safe and only 3rd gear will work, which explains why the vehicle barely moves from a stand still.