Is the solenoid valve inside the transmission part of the transmission?

Our 2000 Toyota Sienna minivan with 150K miles was acting up 500 miles from home. We took it to my dad’s trusted mechanic who said it was the transmission, and sent us to his preferred transmission shop, an ATRA participant. The transmission shop did diagnostics, and satisfied us that we needed either a repair or rebuild. Being risk averse, and given the price differences, we went with the rebuild. 4 hours and ~240 miles after picking up the car, the check engine light came on. It was diagnosed as a transmission code: P0770 shift solenoid E fault. We were told that if this part failed the car would freeze into second gear. We limped home and took the car to a local transmission shop that participated in the first shop’s warranty program. They could find no problem and sent us on our way. 250 miles later (and 150 miles from home) the light came on again. We took the car to our trusted mechanic, who read the same code, but reset the check engine light. The transmission shop said they couldnt diagnose anything from the code number and readout from our mechanic, and that we should drive around again until the light comes on. We did that and another 200 miles or so later, the light returned. We took it to the local (not original) transmission place. 8 days later, they “discovered” its the solenoid valve! But… they say that altough the valve is inside the transmission, it is not part of the transmission. This is because it is an “electrical” part and transmissions are “mechanical”. For only $535 they will be happy to fix the solenoid valve. We explained that when we had the transmission rebuilt, we expected the transmission and everything inside it to work flawlessly, at least for the duration of the 15,000 mile - 1 year warranty. The local shop is now talking with the original shop, and say that if they don’t come to an agreement, that we can deal with the original shop 500 miles from here. Meanwhile, our car is disassembled at the local transmission shop.

Is a solenoid valve inside the transmission part of the transmission? Should its repair be covered under our ATRA warranty?

Please help. We need our car to return to Grama and Grampa’s for the holidays and would like not to lose our shirts in the process.

Modern transmissions have more than one solenoid and in spite of the word games they’re playing with you, those solenoids are inside of the transmission and they are a part of the transmission assembly.

The base transmission is mechanical, true enough, but those electrics are transmission internals and they are what controls the mechanicals.

The word “rebuild” can mean different degrees of that process and often the solenoids are simply reused during a rebuild. Since 10 year old, 150k miles parts are being reused they are prone to failing at any time and the simple act of removing and installing them could cause a problem. In a perfect world, new solenoids would have been used rather than take a chance on well used ones.

As far as I’m concerned this is a warranty issue and they owe you. However, this might take some serious prodding since they’re 500 miles away.

I would think so…Most warranties read “Transmission and internal parts”…

But in todays electronic age, who knows?? A trouble light means nothing really, as long as the transmission is operating correctly…The trouble light glitch could be meaningless electrobabble…

thanks for the clarification. The local shop is supposed to honor the warranty from the original shop. Any tips for getting action?

We’re thinking of getting in writing from a toyota dealer the fact that the solenoid inside the transmission is part of the transmission, as a tool to prod the shop to make the repair. My husband is thinking of offering to pay for the part, but have them pay for labor and all else. After all, they had to disassemble the transmission under the warranty to confirm the diagnosis. So you think that the time to install the new solenoid valve once they have taken the transmission apart should be negligible/very small?

I think Transman will be the expert on this one, but the question of whether or not it is in the transmission may not be the operative question. I think you need to read the warrentee carefully to see what exactly is covered. Does it cover the parts and workmanship of what they installed? There are many many parts in my experience that are only inspected and if ok, are not replaced. This would probably include the shift solenoids. I’ve had the shift solenoids replaced on the Olds and it didn’t require opening the transmission proper. I also had a 4th gear solenoid go out after a rebuild by and ATRA shop and they replaced it no charge. So read the material and you may want to instead negotiate something in between like paying for the part. You can always argue the thing afterwards instead of leaving the repair in limbo.

They should have changed those solenoids, especially with 150k on them. Its part of the transmission and they need to replace them under warranty. Its a $90 part for them. Most transmission shops reuse items like that and send them out the door keeping their fingers crossed they hang on until after warranty. Believe me, you have already paid for them. Unless they can show you something in writing that you signed saying otherwise.


thanks to all. wish us luck!

And get the work done (that should have been done) right away, under their warranty. A transmission solenoid job alone can cost between $800. & $1000. Probably more on a Toyota. That solenoid is a bear to get to and the job is billed out at 7.5 hours.