Torque Converter Lock Up Failure

A 2004 Hyundai Tiburon GT (6 Cyl), Automatic transmission, transmission flush @ 90,000 miles, current mileage 140,000 miles.

Wife got the “helicopter light” a few miles before home, ran the codes (didn’t write them down before I cleared them) and it was failure of the torque converter to lock up.

Trip was about 50 miles each way, visit time was about 8 hours, temps in the 90’s, drive was a combination of high speed (70 mph) and stop and go, outside temps in the 90’s so AC running.
Engine didn’t overheat, all fluids clean and up to level.

I cleared the Codes and have been driving it for the last 2 days, combination of high speed and local but Codes haven’t reappeared.

From the Pat Goss video I’m thinking that it may the time for another Transmission Flush but would appreciate any thoughts.


What was the code?


Sorry, got the usual ECU code, which I jotted down but neglected to jot the source transmission code but it was definately Torgue Converter Lockup Failure.

Many things can cause that condition.

And an actual code points to the possibilities.

I assume your code reader/scanner can’t retrieve history codes?


Just from experience, a failed converter can spew particles through the transmission requiring an overhaul. If it is not due to an electrical or computer issue, I’d have that thing checked. Fluid change on a converter going south will have no impact.

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There must be a rotation sensor on the engine side & another on the transmission side. If either sensor fails the computer may think the TC isn’t locking properly, when it actually is, and the problem is a faulty sensor instead. Probably need a shop-type (i.e. expensive) scan tool to test the sensors though.

Is your transmission configured so that the pan can be drained? If the problem returns, and no other explanation, that’s probably what I’d do, then refill with fresh fluid. If the transmission fluid filter can be replaced, I’d do that at the same time. Even if it didn’t fix the lock problem, at least you’d have fresh fluid and a new filter.

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