Toyota RAV4 Forums banner

Dreaded Transmission/ECM Problem

310 9
2001 Rav4
67,500 miles

I bought this garaged, dealer-maintained Rav a year ago, and have had no problems. Shifted smoothly through all gears.

Yesterday, I put it into REVERSE and it banged hard into gear. I tried it a couple more times, same thing. Oh s**t. Fortunately, the DRIVE gears still shifted fine, so I got it home.

Today, I resoldered all the suspect resistors that we know about.

It now shifts into REVERSE ok, but when I started driving, the shift from 2nd to 3rd was all f**ked up.

I'm not sure what to do, as I don't know if resoldering all the resistors again will help.

Could it be one or more of the resistors are bad?

Can someone recommend a reputable business to send it to to have all the resistors replaced with fresh solder?

Or, any other ideas?

This is my only vehicle, and I've already missed a day of work/pay because if it.
1 - 10 of 10 Posts

· Registered
Joined
·
12 Posts
Discussion Starter · #3 ·
Thank you, eelee!

Was it an exchange or repair? The link you sent was for a repair, and the exchange is $100 more.

Also, I forgot to disconnect the negative battery cable when I removed the ECM box. Can that be a problem?
 

· Registered
Joined
·
3 Posts
I did an exchange but in hind-sight I wished I would have done the repair. The removal/installation video did not say to disconnect the battery, I just did it to be safe. I don't know if it is a problem removing or installing the ECM with power connected.
 

· Registered
Joined
·
50 Posts
Is there a possibility you could get to a local salvage yard and buy a used computer? These Rav4's don't have a TCU. The electronics which operate the transmission are contained within the Powertrain Control Module.

TCM controls JUST the transmission. It's a Transmission Control Module.

ECM controls JUST the engine. It's an Engine Control Module.

However, a PCM controls BOTH the engine and transmission. It's a "Powertrain" Control Module. Engine and transmission together are referred to as the "powertrain".

Many sellers generalize PCM, ECU, TCU, PCU, etc, etc....... because most consumers are unfamiliar with proper terminology used within the automotive industry.

Anyways, that being said, if you can find the correct Rav4 in a local salvage yard, you can use it's PCM in your Rav.

If you want to give this option a shot, pull the PCM out of your Rav. Look at the ID sticker The ID's are as follows:

1AZ-FE 4x4 AT
1AZ-FE 4x4 MT
1AZ-FE AT
1AZ-FE MT

The 1AZ-FE MT identification sticker may omit the MT and just display 1AZ-FE. When this happens, the PCM is used for non 4x4, Rav's which have manual transmissions.

Basically, look for any Rav similar to yours with the same kind of transmission (auto vs manual)........ and the same kind of drive type (4x4 vs front wheel drive).

If you do find a similar Rav at a salvage yard but it has some different features than your own Rav, the PCM can still be used as all other features are controlled thru another set of letters called a BCM.


Good luck.
 

· Registered
Joined
·
3 Posts
I would not be pulling a ECM from a wrecking yard if it is a 2001 to 2003 RAV4, unless you are feeling lucky. Toyota initiated a CSP and extended the warranty on the 2001-2003 RAV4 automatics because of the ECM problem. Unfortunately the extended warranty ended Aug 16, 2021. (See attached) I have been looking for another 01-04 RAV4 and two of the seven I test drove had the ECM problem.
 

Attachments

· Registered
Joined
·
12 Posts
Discussion Starter · #9 ·
UPDATE:
Pulled the PCM out, carefully resoldered the suspect resistors on the circuit board (used a tutorial I found on YouTube), reinstalled it...and the shifting problems were worse, and now included triple shifts from 2nd to 3rd. Incredibly dismayed.

However, I did some more research and discovered that you must drive the vehicle for a while to let the computer readjust to all the engine and transmission input signals. Drove it around town at 3am for about 45 minutes. Stop and go. Stop and go. Got on the interstate and used passing gear. Now shifts fine.

What an ordeal!
 
1 - 10 of 10 Posts
Top