Code P0770 (check engine light)

[CalessaSSracer]

Shift selonoid? what should i do now?
The truck is shifting AOK, should i start freaking out now?

[Brian R.]

See the description of this DTC in the FAQ thread post:

http://www.automotiveforums.com/vbul...5&postcount=28

P0770 Shift Solenoid E Malfunction

Solenoid E (SL) is the torque converter lock-up solenoid. If the torque converter is a little slow locking up, it will set this code. May only be a one-time thing owing to a small particle of something getting jammed in the solenoid. The code may disappear by itself.

If it doesn't right away, check out the color of your tranny fluid. If it is pretty much red or brown and smells ok, then flush the tranny and see if that gets rid of the code. If not, pull out some fluid and add a bottle of Seafoam Trans Tune and run it for 1 or 2k miles. Then flush the transmission again. Check if the code is gone.

If this problem persists, I've been told you'll have to replace the E-solenoid.

There is a Service Bulleting (EG006-00) issued for '00 Siennas on this problem. They get a new torque converter to fix the problem permanently.

The following discussion was submitted by csaxon:

The ECM uses signals from throttle position sensor, airflow meter and crankshaft position sensor to monitor engagement of Torque Converter Clutch (TCC).

The ECM compares engagement condition of TCC with lock-up schedule in memory to detect MECHANICAL trouble of lock-up solenoid, valve body and torque converter. A P0770 trouble code is set when TCC lock-up does not occur during appropriate speed, or lock-up does not release at appropriate speed.

Possible causes are:
* Solenoid is stuck open or closed.
* Valve body clogged or valve stuck.
* TCC malfunction.

There are simple electrical tests to check the solenoid and plunger but the transmission pan must be removed to gain access.

As Brian suggests, if you haven't had your system flushed or changed in awhile it may help but I'm not sure that's cheaper than actually removing the pan and checking the solenoid.

The Toyota service tech can check the system without pan removal with his analyzer.

[CalessaSSracer]

Yeah i saw the list!
I will go ahead & flush the system as im hitting 70k and its never been serviced there.