Thank you, Jake, this is very helpful. I went ahead and added your pictures to the posts.

 

Or Dallas, Oregon

 

Thank you for such valuable info. I found the video and I was following it. I am an electronics tech but had to have my ecm repaired as I couldn't find the problem. My cousin have the same car with the same problem (only that hers is 2003) and seeing the video, I tried it without success.

I guess that it is not the same in all cases, as it improved a little, but the problem is still there and the tranny was replaced already a month ago. Anyway, I opened up my repaired ecm to confirm and those resistors did not look like it was resoldered.

I will still try it in another ecm of one of my friends. He bought his car at the same time I bought mine, but his is showing the problem now. I will post any follow up.

regards

 

Just bought 2001 RAV4 135k miles for father in law. On the original un-updated ECM but no problems with transmission. The car will be out of state from me and away from my close watch. So I thought I do all preventive work on it including this ECM.

Had Toyota update the software per 60I campaign. Now having an electronic tech at work to touch up these solder joints. He provided some interesting info I thougth I share

1. When I told him about the resistor solder joints. He immediately concluded the bigger resistor's higher inertia in a car that is bouncing around might be the cause.

2. He said these circuit boards use lead free solder which becomes brittle. He used leaded solder for touch up. He said leaded solder responds much better to shaking. Using his words "it behaves like its melting"

 

That's interesting. The day mine failed I was coming back after a lot of driving on crummy forest roads and doing a lot of bouncing and shaking.

 

I had my ECU repaired by chkengine in Brooklyn in Oct 2012 and the car has run perfectly ever since. But the other day it wouldn't engage Reverse (Drive was fine). I left it and came back in 2 hours to try again, but this time the car wouldn't start (lights etc all worked, but nothing from the starter). I checked that there was battery voltage at the starter and that the ignition lead at starter showed voltage when turned to start position, and determined it had to be the starter. I replaced the starter, but on initial re-start attempt it didn't work. But on second attempt it did start AND engaged Reverse successfully. But then an hour later, it wouldn't start again (the starter doesn't operate when the key is turned). Everything checks out at the starter terminals. So I'm suspicious of my ECU.

Does anyone know if a faulty ECU could affect the starter function?

 

Thank You!

Thank you Jake! After parking our 2001 RAV4 for about 6 months, I was experiencing very erratic shifting. I had no issue before parking. I thought it was the transmission. I don't have money to get that repaired and was stressing a bit. Then I found your video which showed me a quick, easy, free fix.


All I had to do was reheat the existing solder on those 6 transistors which fixed the issue.

May God bless you!

 

Got trouble with the ecu on my 2003 model, and found the solution to the problem in the youtube video and this thread. Took a closer look at the ristors under a microscope before I resoldered them, and you can see the small crack on the photo attached her. Shifting is now ok again, even though there still is some juddering under heavy load, will replace the atf fluid now and hope for the best that not discs in the atf allready is damaged. Thank you very much for this easy solution!:smile

 

Got trouble with the ecu on my 2003 model, and found the solution to the problem in the youtube video and this thread. Took a closer look at the ristors under a microscope before I resoldered them, and you can see the small crack on the photo attached her. Shifting is now ok again, even though there still is some juddering under heavy load, will replace the atf fluid now and hope for the best that not discs in the atf allready is damaged. Thank you very much for this easy solution!:smile

View attachment 35418

Hmm, still problems between 2-3 gear, + engaging reverse which has a lag of about 2 seconds. Maybe I should have measured the resistance of the resistors, and not just resoldered them?

 

ECM/Transmission problem for 2001-2003 RAV4

Hi: This video on how to repair your ECU is very helpful and definetely a $$$$ saver. My 02 Rav4 began having this issue with erratic shifting at about 120,000 on the odometer. It feels like it wanted to take off from second gear and also when engaging into reverse it makes a very noticeable sound and vibration. After searching the web, answers began to appear right away pointing to the same symptoms my truck had.
I ran the vehicle with this condition for about 200 miles. Found this guy in ebay that makes the repair for the ecu for $150. For this price and with so many postings indicating the same diagnostic I proceed to send my ecu. Three days later, received the unit, install it and problem solved!!!!!! So far my 02 has 173,000 and still runs like if it was new.
Bottom line, if you are having this issue, I will recommend fixing your own ecu if you feel you can do it or go for the alternative I did. Just avoid dealers which will charge you ridiculous amount of money.

 

hi ponsai03
I have same problem with my rav4 2003 , can you please send me that link in ebay for repair ecu ? thanks
email : ramsey2411@gmail.com




regards

 

I MENTIONED THIS SOMETIME AGO AND NOBODY PAID ATTENTION TO IT.

besides 6 resistors were re-soldered, there is a transistor. (B906) right next to the 820 resistors also re-soldered.

Matter of fact, since the ECM was soldered using non-lead, and the bigger the transistors/resistors may not get good connection, why not resolder them all. Flip the board over and resolder the big ones too.

 

What makes you all so sure that the solder used in those ECMs is lead free? Because it is not. It looks like that because of the process used to assemble the unit. The resistors is just part of the problem, not the problem itself. Those are current sensing resistors, used to record the current amount passing to the solenoids and then populate the transmission adaptation table memory with proper codes for a better shifting. Resistance value is low (0.33 ohms) as to not significantly lower the current going to the solenoids, while sensing the voltage drop across the resistors to calculate the current draw at different times.

I see that there are still many "shops" on trial and error (playing) with these units. That is why we receive so many units poorly worked out and needing extra repair, specially coming from eBay.

Please guys, be careful who you buy a service from on eBay. Some units that many of those "shops" tried to repair are then sent to us by those customers in a second attempt to repair their ECMs.

Some units are left unrepairable as there are some of those "shops" that after doing their non-working job, they cover the circuit with some epoxy, leaving the unit impossible to be reworked without damaging the circuit board. I have seen others putting underrated parts, like a 25v capacitor, where the original is 50v. They must be saying, "well, it is a 12volt system, so a 25v capacitor will work". They do not even take in account the internal switching power supply of the ECM, that generates voltages higher than 25v. Some other put a lot of solder in the grounds, taking as true, the myth of the poor ground problem in the screws area. Summarizing, they are just playing to make an easy buck and won't refund a cent when it fails, giving the excuse that it must be the transmission. In some case, it is the transmission, but in the majority of the cases, it is only the ECM.

 

2001 rav4.. hard shift between 1 &2 .. real hard shift.. Followed directions and re-soldered the resistors and the transistor cold solder joints for good measure.. Put it back in and same issue.. Hard shift.. Scratched my head and wondered if i missed something so i removed the solder i put on and did it all again.. Took it for a drive and same thing.. However the next day it started shifting like a new one.. Guess that computer had to have a chance to get used to the new commands .. THANKS for the "it works DIY" ..

 

Hot Air Reflow Station

Dear Friends,

Mine RAV4 2003 have just started behaving weird, with ackward gear shifting plus a slipping sensation, so I am trying to find someone here in Brazil that could service the ECU board.

I found out I will have to do it myself, so after some research, I found a similar situation where the guy used just a hot air rework station and it looked like extremely simple.

Please check the video on Youtube:
https://youtu.be/lgcZ7LYKb_w

Do you think it could work?

 

Why not use the video shown in this thread as the one u posted is for a different vehicle.. That being said.. Hot air works just as well or better than a soldering iron.. Problem i have found with hot air is getting used to how much heat u are applying. I have seen very small parts "dislodged" by hot air gun "on the opposite side" by putting it too close to the part and heating both sides at once.. CAREFUL is all this amateur could add.

 

Brucecb12,
I posted a video of another ECU as It was the only example of ECU being serviced with hot air I could find.
As I have decided I will fix it myself, I would like to know if you have any issues regarding the lead-free solder. Do I need to reflow/resolder with lead free solder as well? The fusion temperature is 30 to 40'C higher when compared to Tin/Lead solder alloys. Do I need to add more solder or just melt the solder that is already there?
Many thanks.

 

Sorry to interrupt, but I recommend staying away from lead-free solder. It is more brittle and more likely to crack, especially in an automotive environment. Yes, reflow with a little more solder to each joint, but don't overdo it.

 

I have a 2001 Rav4 with the typical shifting complaints. Tried the resoldering of identified parts, as well as everything else that was big enough to work with, no change. Took it to the dealership, they told me there was nothing wrong with the ECM, no codes and no updates needed, and that the transmission likely needs to be replaced. Seems like they didn't believe me about the ECM problem, though they did dig up the TSB on it. The shop tech told me they've never replaced an ECM.

What do you guys think, is it really the ECM if they've already had a look at it and think it's ok? The other thing to note is that it has 240k on it.

Does anyone know of a reputable place in Canada to get the ECM repaired? I've checked with a couple of places in the states and it would be over $400 by the time you add shipping.

Thanks for any help!

 

I'm in BC as well and sent mine to Home and have been driving it for a few years with no problems. I am confident in these guys as they have repaired many others from this forum.

Unfortunately with our current low Canadian dollar it ads up.

As for taking it to a Toyota dealer mine wanted to replace the transmission and ECU = big $$$$. My failing ECM also generated no codes.

The $300 or whatever it was turned out to be the best money I have spent on this vehicle.

 

my ecu of 2004 rav looks totally diferent to the ones fixed on utube.the part no is8966142a50.anyone has knowledge to fixing this ecu.the original one was selecting 2 gears at the same time and the car would pull away very heavy and shoot to third gear.putt in a second hand one from another vehicle and had it programmed to my car and now the car reves high from second to third and feels like its slipping bt the mechanic said the gears aren't slipping.tried putting the old one back and now the car doesn't even idle.dont no what they done

 

tengo una RAV4 2001, tengo problemas con la ECU, es recomendable que la repare yo mismo o la envie a reparar que opinan ustedes

 

Pues repararla tu mismo no es recomendable, a menos que tengas conociminetos avanzados en electronica.

Yo recibi una que el cliente la trato de reparar el mismo y tuve que remplazarle mas piezas de lo normal 9si, no es solo soldadura) y tambien le remplaze el microcintrolador (MCU) de motor, que tiene 80 pines, que lo dañó con el cautin. El trabajo cojio el dia entero.

Si deseas te puedo brindar el servico. Veras la informacion en el enlace al final de este mensaje.

Saludos,

Richard

---
ENGLISH VERSION

Well, doing the job yourself is not recommended, unless you have advanced knowledge in electronics.

I received and ECM from a customer that he previously tried to repair himself and I had to replace more parts than usual (yes, it is not only soldering) and also had to replace the engine micro-controller (MCU) that has 80-pins, that he damaged with the soldering iron. The job took the whole day.

If you wish, I can offer the service. You will find the information at the link at the bottom of this message.

Regards,

Richard

http://www.facebook.com/Rav4Repair

 

Hello- I am purchasing a 2002 RAV4 for my daughters first car. They are currently replacing the ECU (not sure if they are sending it out or what) which is great but I have no way of knowing if it was bad for a while and has caused any damage to the transmission (115K miles on it). I will probably end up sending out ECU to reputable shop for repair just to be safe but in the meantime, is there anything I can do to check for tranny damage? drain fluid and look for metal shavings is about all I can think of. Look forward to helpful responses. Thanks very much.

 

This seems to be an ongoing issue and it finally struck my RAV4 too, at just over 200KM. No issues before, just two nights ago a first jerk when going in reverse. Then yesterday the typical: rough shift in reverse, rough shift to 2nd and occasional stops and shakes mid-way through the 2nd with hesitations seeking to shift to 3rd.

For me, in Toronto, my options narrowed down to two, and I was ready to choose either of them as they are both verified and good pros. Depending on your location, you can deal with Neutron Electronics in Guelph, 519-766-6993 or Rus in Vaughan, Hwy400/Hwy7, 416-660-8414. I chose Rus as driving to guelph was tough on a tight schedule. He had the 10mm wrench and Phillips screwdriver ready. He fixed it in no time, test-drove and offered warranty. He helped many and I was looking at an "as brandnew" computer teaching it the shift pattern again. Kudos to both for the positive attitude and once again another slap to the dealerships asking for many hundred$ to fix something that should by now be a subsidized recall/maintenance issue.

 

RAV4 1998 ECU PART No.

Guys,


Greetings! Need your urgent help please...I have 1998 RAV4, but unfortunately, the Engine Control(ECU) crashed. Now I am planning to purchase brand new parts here in KSA. But they are saying that the part no. between Philippines and KSA are different.


The part no. is 89661-42270, Engine Control...Please need your kind help...thanks a lot.....

 

accessing the ECU board

I have a 2008 RAV4 V6. I want to access the ECU board to take a look at the chip condition, but can't get pass the housing/enclosure. Any recommendations on how to get to the board?

Thanks!

 

I have a 2002 rav 4 which seemed to shift fine no problems with slipping then 1 day after parking overnight I leave to go to work no problems for about a mile then my transmission starts slipping like crazy I get home and check the fluid and it is extremely high on the dip stick which leads me to believe it's not leaving the tranny pan does anyone have thoughts about this can a bad ecu be the problem?

 

Hello All,
New here, 1st post. Just had to say Thank You,
I have 02 Rav4 with only 52,000 mi. Needless to say its not driven much. It started with the hard shift into reverse, drive. Progressed into serious shifting problems. Brought it to the dealer, where they updated the ECU. Which after reading all the horror stories I didn't have much hope on it fixing the issue. The update did nothing. I'm sure the tech who parked the truck after updating it noticed it didn't help. You would think they'd call to inform me..lol So I brought the truck back home and just pulled the ECU, thanks to youtube and your post. I'll keep yas updated, after I repair it.
Thanks again .