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My 1993 TT automatic won’t shift into 2nd gear. I can drive it but I have to start it in L and manual shift it up to Drive. I brought it to a transmission shop thinking it’s just the shifting solenoid but apparently the solenoids are fine. He thinks it’s an electrical problem or the ECU. Does this sound right?

Has anyone else experienced this with their automatic? Can someone recommend a mechanic close to Jackson, NJ.
 

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This

is probably your biggest concern. This will happen at some point...no matter the condition of the car. It'll happen to the low mileage ones that sold for 160K as well as a high mileage supra.

Ask the previous owner if an ECU service was done, and if not be prepared to send your ECU off to Tanin Auto Electronix | Shop For Auto Electronic Repairs, Sales, and DIY Parts.

My dad's NA supra because a brick due to a leaky capacitor that damaged the board. The were able to fix it and clean up the board.
I sent mine in (TT 6spd ) and my capacitors were leaking but hadn't damaged anything.

Pretty much everyone who owns a supra should do this as a preventative measure at this point. Stock ECU's are expensive...that is if they're even made anymore (I'm not sure)
Hey there,
I have a 6 speed, but just earlier today I saw this post which may be of interest to you, in case you've not already solved this shifting trouble. Anyway, good luck.
 

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This was the thread that it came from.
 

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When I swapped my ECU out for a standalone I had to wire in relays in my harness so not 100% sure but there may be relays you want to check into. that could just be built into the automatic ecu but not sure as I’ve owned 2 autos and haven’t ran into that issue
 

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Id do cheapest thing and find a auto ecu(not the Main ecu) transmission has its own which is next to the cars ECU under passenger feet carpet.
I highly doubt there is a separate transmission ECU, you either have an auto ECU or a non auto /manual ECU
I've never seen or heard of this .
 

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My 1993 TT automatic won’t shift into 2nd gear. I can drive it but I have to start it in L and manual shift it up to Drive. I brought it to a transmission shop thinking it’s just the shifting solenoid but apparently the solenoids are fine. He thinks it’s an electrical problem or the ECU. Does this sound right?

Has anyone else experienced this with their automatic? Can someone recommend a mechanic close to Jackson, NJ.
Did you do a resistance check on the solenoids? the solenoids are made of hydraulic plates/washer with springs, that sends an electronic signal from the magnetic coils within the solenoids, this signal is send to the ECU , to switch gears , based off of engine load, through out 20+ years of the trans oil being polluted with the clutch pack friction materials, it will clog the tiny mesh screens and cause an incorrect voltage spike, causing it not to change gears at the correct load.
You can try replacing the old trans oil , and see if it helps? and inspect the wiring inside the transmission box, which is visible when you un bolt the pan. also , drain all fluids from the lines that lead to the cooling system m flush it out and use a synthetic Dex 5 or 6 fluid. Follow the correct procedure in the TSRM
 

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I had a problem similar to this. The MANU light would randomly come on coupled with the automatic transmission not shifting automatically. As I recall, I could still shift the transmission manually.

The problem was the main engine ECU. I replaced it and it resolved the issue.
 
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