hello5460

(2007 ES350, 241k miles) Ive been having transmission issues lately, searched the forum and found nothing directly related to my problem. One day I was driving around 70 and the trans slipped when it was about to shift (5th to 6th i think) and the engine revved all the way up. After this the car can only go up to 3rd gear (4th and up and engine revs like its in neutral). Engine gave codes: P0746, P0776, P0796, P2714 which are pressure control solenoids A-D stuck off. Towed the car to my trusted mechanic and he did a few trans flushes, gasket, and filter and ATF replacement. Car still wont shift past 3rd gear so Ive been using it for city driving in sport mode in 3 (only uses gears 1-3) since I need a vehicle right now for work. Will driving it like this make the trans worse? When my mechanic flushed the trans he found a pink piece in the pan that looks like wiring of some sort.

My mechanic says that multiple flushes will fix the issue. I think that this pink piece is from wiring so it may be worth replacing the wiring harness for the solenoids. What are your thoughts? I would like to repair this issue, buying a new transmission is not in my budget and considering the year and mileage of the car, I may as well buy a new car. What are my options? Thank you I really appreciate any input!

Clutchless

That just looks like wiring insulation.
It may more likely be stuck solenoids than broken wiring especially since that is what your codes indicate.
I think there are solenoid kits for this transmission that replace all at once.
Just replace them.

Look at this article about the U660E transmission, it starts on page 8.
http://www.gearsmagazine.com/resourc..._all%20nbg.pdf

ESh

Tell the mechanic that multiple flushes won't fix the issue. I think the problem is one of the solenoids or the wires to that solenoid.

So, we have three tables here:








As you can see in order to operate the C2 clutch for 4-5-6 gears you need the solenoid SL2. Without it those gears won't work. So you have to remove the solenoid and test it. If it is bad then replace it. If it is good then check the wiring. Also, since you're there check all the solenoids just in case.

nevernu

what do c1, c2, b1 etc refer to?

ESh

C1 clutch for the first 3 gears
C2 clutch for the next 3 gears
B1, B2 and B3 are brake clutches.

Wilson2000

Just a quick thought...If your solenoid wiring is missing a piece of insulation, the wire could be shorting to ground and causing the solenoid issue, but your transmission tech should have been able to identify where the insulation came from.

I guess he is hoping the solenoid is sticking due to dirty fluid and the flushing will un-stick it. Sounds like wishful thinking. Does your tech have a good reputation?

nevernu

I may be off here but the wiring diagram shows SL1 as having a red wire.

giogel

hi,
i have same codes and same problems, can you help me?

hieut007

Dear Nevernu, thanks you much for the trannsmission diagnostic information. I have similar problem and will take another look at the solenoid. Also, I see that you have very clear electrical wiring diagrams. Can you refer me to a good automotive reference provider for similar repair information? I am looking to find out the diagnostic software is unable to connect to the ECU via OBD2. There is power but no connection.

Thanks again.
Hieu Tran

nevernu

Hi I'm not certain what you are asking but it seems you can't connect via the DLC3, perhaps this will help. I saw this procedure about connecting Techstream, your software may be different. I also included a pinout of the DLC3 for possible troubleshooting.

1. PRECAUTIONS WHEN USING TECHSTREAM (a) When using Techstream to troubleshoot the smart access system with push button start: Connect Techstream to the DLC3 while the engine switch is off, and turn a door courtesy light switch on and off at 1.5-second intervals until communication between the tester and vehicle begins.

hieut007

Dear Nevernu, thank you so much for the DLC3 wiring information and Techstream connection info. I will try as you've suggested. This weekend, I will be replacing a couple of U660E valve body solenoids with new ones to correct the 4, 5, and 6th speed shift issue (no shift) based on the super helpful information you've shared on this thread. Hopefully, the 300K mile transmission will run after the service and it will allow me more time to diagnose the ECU communication issue as it doesn't allow me to connect to reprogram for TCM to relearn. I already installed a valve body Zip kit (in hoping that it will improve the line pressures but that was not the root cause) and it called for reprogramming of TCM that I hadn't been able to do. FYI, the Techstream connects to my daughter's 2012 car but not to my 2016. So I think there may be a wiring issue somewhere. I can't connect to it with my handheld OBD2 diagnostic tool either.

Thanks again for the immensely helpful info. With your vast experience, your references are very concise and directly addresses the problems and the required corrective measures. Even if I can't get my car problem fixed at home, I have learned a lot from this thread.

Nevernu, once more, thank you so much.
Hieu Tran

nevernu

hi thanks for kinds words but I simply have access to the service manual for the gen 5 es350 2007-12 vehicle and just basic dyi skills. I try to provide just the manual info unless I have done something myself. I notice you say you have a 2016, so remember that any manual info i provided is for the gen 5 es and may not be applicable to your gen 6. anyway good luck!

hieut007

Dear Nevernu, I sincerely appreciate your attention to details and helpfulness in providing the added reference wiring diagrams. You have shared enough base information for me (and others) to form an adequate understanding of the U660E transmission operation and possible solutions to try to manage the problem repairs. There are some minor differences between the vehicle series but not significant enough to affect my problem situation. Thanks again for sharing your knowledge.
Sincerely,
Hieu Tran

pearl93'ls

I have the same problem with my 2008. I only had the first 3 gears. The fluid was original. Even tho dealer serviced from new they never touched the transmission. So infuriating! The fluid was so Black. However other than a little clutch material on the magnets in the pan. The pan and fluid was clean as can be. No metal! I changed all the solenoids and now the transmission is stuck in a limp mode. I was curious if the transmission had to be reprogrammed or something now. The car is in worse shape now than before. I changed these with just jackstands and it was a chore. I hate all my efforts went to waste

hieut007

Dear Pearl93,
I replaced a valve body ZIP kit and two solenoids that affect 4th, 5th, and 6th gears. No improvement yet. The relearning command was not an available option using Techstream. Been using info generously provided by Nevernu. Couple weeks ago, when I went to the dealer to arrange for a reprogramming service, I picked up a hint from discussing with the advisor that the error codes must be cleared first before the relearning procedure is allowed. I don't own the service manual for the car so perhaps that is a major issue for me. This weekend, I'll check relearning again and I will also have an assistant available to command test the solenoids from laptop inside car so I can listen for click inside the transmission with my stethoscope from under car. If they click, then the problem (valve body or clutch pressure) is too deep for me to deal with further. I'll buy an used/rebuilt transmission. If it doesn't click, I'll check circuit continuity from outside transmission after removing the TCM to see if connector contacts are good. If good, I'll replace the possible faulty TCM. If Nevernu get this post in time, may be he give some thoughts on what I'm about to do to see if reasonable. Thank you.

Regards,
Hieu Tran