Overdrive Light Flashes Options

[roelamizzle]

My Overdrive Off light flashes on and off slowly, (about every 3 seconds) while I drive. Does anyone know what could be causing it? or how to fix it? The guy I bought the car from said it was originally an automatic but was converted to manual early in its life and he didnt know what was causing it to flash.

[Bitter]

he didnt complete the swap, you need some resistors of the correct value wired into the trans harness so the PCM is fooled into thinking that the trans is still there.

[roelamizzle]

great, how do I find out what resistors to buy and where would they be located?

[netrata]

Or you can buy a 7afe manual transmission ecu and replace the auto ecu. I don't know if it has a different pinout out or harness connector like the 4age ecu's though. If you need the m/t ecu I got one that I don't use anymore.

[roelamizzle]

where is it located on the car, so I can see what I have to work with or better yet, how much work I have ahead of me.

[Bitter]

Or you can buy a 7afe manual transmission ecu and replace the auto ecu. I don't know if it has a different pinout out or harness connector like the 4age ecu's though. If you need the m/t ecu I got one that I don't use anymore.

its not that easy, you'd have to change the connectors, the AT pcm has a different wiring harness. so in the end you'd have to repin a new connector block or wire up a chopped block form an MT car. big pain in the ass.

i dont know what resistances off the top of my head, look in service information for the specs on the trans electrical, theres certain values the PCM expects to see.

[netrata]

roelamizzle, the ecu is located behind the center console, closest to the gas pedal (look to the right of your gas pedal it is that metal box with wires running to it). And also, are you able to salvage out another main wire harness from a 6th gen celica st with manual transmission? This could help you if you don't want to repin the connector harnesses and solder a bunch of wires since Bitter said that the pinouts are different between the a/t and m/t. Try getting another harness, I would think it would be an easier option. But make sure you label which connector goes where on the car.

[Kwanza26]

roelamizzle, the ecu is located behind the center console, closest to the gas pedal (look to the right of your gas pedal it is that metal box with wires running to it). And also, are you able to salvage out another main wire harness from a 6th gen celica st with manual transmission? This could help you if you don't want to repin the connector harnesses and solder a bunch of wires since Bitter said that the pinouts are different between the a/t and m/t. Try getting another harness, I would think it would be an easier option. But make sure you label which connector goes where on the car.

Repinning the ECU connectors is easier than removing the engine harness...

[roelamizzle]

Ok guys, thanks for the info, I'll dig in and see what I can do to fix it. In the mean time should I be concerned about this? Is it something that could be damaging my car?