1989 Buick Electra Park Ave 3.8FI Auto 4T60/th440. Front wheel drive. 130K miles. Vehicle seems fine until it drops out of cruise on the highway. Acts like it has no power for a few seconds. It seems to do it regularly but started intermittent with acting up like it couldn't decide to stay engaged or not. I've checked for codes, code 39 TCC solenoid circuit failure. My question is where is the stupid thing? Did they put it on the side where you can't remove the cover or were they merciful and put it where the filter change access is? Has anyone done one of these in the car if it'* on the side? Anybody have luck with new fluid and Trans medic with this issue, maybe unstick/unclog something? Inquiring minds and all. Or am I looking at learning how to rebuild one of these?

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Home >> Buick >> 1989 >> Electra Park Avenue V6-231 3.8L VIN C SFI >> Repair and Diagnosis >> A L L Diagnostic Trouble Codes ( DTC ) >> Testing and Inspection >> Manufacturer Code Charts >> DTC 39

DTC 39

Code 39 Chart:

Code 39 Wiring Diagram:

CIRCUIT DESCRIPTION:

The ECM controls TCC operation by grounding CKT 422 through the quad-driver.

Code 39 will set when:

^ No Code 29 is present.

^ Brake switch is closed, "OFF".

^ TCC is commanded "ON" by the ECM.

^ Vehicle is in 4th gear.

^ he engine speed to vehicle speed ratio is outside of its window of operation.

^ All of the above for a time greater than 30 seconds.

NOTE: Because of all the possible color code combinations used on electrical wiring diagrams, always refer to ECM CONNECTOR IDENTIFICATION under ELECTRICAL AND ELECTRONIC WIRING DIAGRAMS for correct color code identification of circuit.

TEST DESCRIPTION: Numbers below refer to circled numbers on the diagnostic chart.

1. Checks fuse, brake switch and B+ circuit to the TCC solenoid.

2. Checks availability of B+ on CKT 420.

3. Electrical circuits have checked out. If there is a TCC engagement problem, it is a transmission problem.


DIAGNOSTIC AIDS:


^ A Code 39 in combination with a Code 38 would mean a problem with one or more of the following components. Fuse, CKT 639, brake switch or wire before the splice. A single Code 39 is the result of a wire or CKT 420 problem between the splice and the TCC solenoid, CKT 422 problem between TCC solenoid and ECM, poor connection to ECM connector, or possibly the ECM.

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What carfixer007 said ^^^^^^^

. . . and:

How many miles on it?

How many miles have you owned it?

After doing my homework with all the great advice and gobs of knowledge. That made me feel powerful. Look out. Lol I found out there was basically nothing to lose in a juiced transmission tune up. New filter, DexVI gallon of fluid. I added 8oz seafoam , 16oz mechanics secret, 20oz lucas trans fix. Also one 2oz friction modifier. From the looks of the magnet I am just buying time. It drives and engages OD and stays in cruise. It downshifts and acts like a normal car again. I came back to post this to give others hope. I thought for sure I was just wasting money. The car has never shifted this well. I have no clue the last time it was changed. The looks probably never. I bought the car for $500 for my elderly mom. It will continue to get her around thanks to all.

Quite a cocktail of fluids there, I'll be curious how it holds up!

Quite the cocktail indeed. That transmission might be suspected for shifting under the influence. It certainly will be interesting to hear how it works out.