PO773 Mystery

[golfinator]

My 97 had its first cel 7/08 at 140k mi. Autozone scanned and showed a PO773. Figuring it was not affecting emission, cleared code before emissions test and passed testing. Did the same before '09 test- same Autozone, same PO773, same testing station. Cleared code, passed test. Of course, the cel remained on ater 2-3 trips, until I had to disconnect battery for one reason or another. This year, no visit to Autozone to confirm code, just cleared cel before test. However, this time went to different test station. Test conducted differently from other station- they shut car off 2x (don't recall previous test shutting car off). Had no cel before test. Avy failed test. Test showed P1410 and cel was on after test. Went straight to Autozone with cel on. Readout showed only PO773 code. Next day, not knowing which, if either, code was correct, replaced the EGR sensor and added can of SeaFoam Trans. Treatment to tranny. Drove enough to let SeaFoam work, drained and refilled tranny, then cleared cel. Made 5-6 trips- NO cel. Back to emission station that failed avy, retested, PASSED with no codes. Is it possible (1) Autozone's scan tool read the wrong code both times, or (2) just a coincidence that, shortly before or during this year's test, avy got a 1410, but SeaFoam treatment had cured the 773, or (3) the original test station did not pick up the 1410 or 773 (if needed to pass emissions) because they didn't conduct the test correctly. Your guesses?

[golfinator]

Well, after 1 week and about 14 trips, my cel appeared and read a PO773, so I'm off for another can of SeaFoam and quarts of trans. fluid.

[GreatAvalon]

man that is wierd. i have no clue, i've never heard of that happening before. good luck!

[sonic2wb]

hey i jsut dug around in the archives and found this

11-21-2006, 06:59 PM
The manual states this code is related to a problem with Shift Solenoid Valve SL (solenoid E). From what I can figure out this eventually controls lock-up of the torque converter. The ECM is supposed to set the code if this solenoid has a resistance of 8 ohms or less when energized or 100 ohms or more when not energized. Or it could be a bad electrical connection/wiring causing a high ohm reading or bad ECM.

Being far from an expert on automatics, I still wonder if the manual states the trouble code refers specifically to this solenoid (whatever it does), why can’t the dealer test it and the wiring, or just replace the part. Is this one of those, the code does not tell the whole story issues.
kentk1
12-04-2006, 02:08 PM
I think we are zeroing in on my specific problem. Last week the car exhibited the problem again after running for 30 minutes on the freeway. I called my mechanic and he came out with his laptop and we captured the state of the problem. The car was in 'fuel cut off' for some reason and we were pulling a P0773 code from the transmission. At this point, the engine was running but would not accelerate due to the 'fuel cut off' state. We touched the wire harness to the tranmission and all of a sudden, the engine was running fantastic, so we feel that there is a short in the wiring harness to the transmission. Its at the shop....again...to examine and test the wiring.
kentk1
01-10-2007, 02:20 PM
Well, just an fyi...turns out that replacing the wiring component inside the tranmission as well as outside to the computer solved the issue.
axle1320
06-02-2007, 05:55 PM
I had posted some time ago about my issues with this shift solenoid E code - P0773 on my 1998 Avalon. Had a local shop replace the shift solenoid, CEL came on the next day. When I took it back to the shop he disconnected and cleaned all the electrical connections to the transmission - I think he said there were four of them and one of them had some oil around it. It has been ten days now and no CEL. So maybe cleaning the connections ought to be the first step when this code shows up.
Chuck


maybe this is ur issue

[sonic2wb]

heres the link from the archive

Transmission Problem 97 Avalon

[golfinator]

Thanks Sonic. I just did my 2nd Seafoam treatment and fluid replacement, hoping there is something messing up the SL valve. I think the SL problem is supposed to show a cel after 2 trips. After the 1st treatment, it didn't come on until after 10 trips. If this doesn't solve the cel, I'm back to the wiring and sol. replacement. Since I don't notice any lack of performance in trans. shifting and locking, I've been taking my time and going with the easiest solutions first. BTW, ECM checked out fine.

[golfinator]

After a long 400 mile trip, my cel had not come during the last 20 short trips, but did so yesterday I was hoping the seafoam and fluid changes had taken care of whatever was triggering the cel.