Overdrive off light is now flashing

[sb2463]

Sometimes, my 03, when traveling around 40+ MPH the Overdrive light starts flashing. I can't stop it from the shifter. I can stop and it will stop. The car is in Overdrive still when this happens. It seems to change from OD to standard from the shifter however. Crazy. Could it be something loose?

[tbone]

Check the wire at the shifter. Maybe it's pinched.

[Chevyguy]

That's the transmission screaming for help!!

Flashing OD light signals a fault in the transmission control. Should be able to read the codes with a OBDII reader.

[RF Overlord]

It seems to change from OD to standard from the shifter however. If the OD light is flashing, you have no OD. What you're feeling when you press the button is the torque converter unlocking.

The repair bill goes up exponentially the longer you drive it like this.

[RacerX]

What you're feeling when you press the button is the torque converter unlocking.
Saywhahuh??? :confused:

[RF Overlord]

Say just what I said. Even though there's no 4th to go into, the torque converter clutch still locks up. When you hit the OD off button, that also unlocks the TC, so what he's feeling is not the drop from OD to third.

[RacerX]

That can't be true since you can actually data log the convertor locking with OD off. I actually monitored this because I had an issue in 2nd with tc lockup.

Possibly the diode in the tranny???

[a_d_a_m]

I had this happen in my '02 MGM back in 2006. The transmission temperature sensor or something had completely ***** the bed. I had that replaced, then another thing went bad, then the whole transmission just went south about 6 months later.

[RF Overlord]

RacerX, I'm not saying you're wrong, but I know that when I hit OD OFF when I'm in OD, I feel 2 "downshifts": one from OD to 3rd, so the other has to be the torque converter unlocking.

[RacerX]

I'm sure our tunes are completely different also. :beer:

Hey OP, SB2463, do you have any dash warning lights comiing on? I would have those codes read asap if so.

[RF Overlord]

Prolly just a little.... :)

[Baaad GN]

OHHHHHHHH thats baddddddddddddd, bet it's gonna cost thousands!!!!!!!!!!!

[RacerX]

Do the easy things first. Check your fluid level and make sure fluid doesn't have a burnt smell, get your ODB codes read, jack the car up and see if there's loose connectors or any wires that could have rubbed through. Might be worth a tranny flush if no damage has been done yet. If you're getting hot fluid temps, you likely have clutch plates slipping and would need a rebuild on yours or get a used/refurbed trans.

[scruff]

Sometimes, my 03, when traveling around 40+ MPH the Overdrive light starts flashing. I can't stop it from the shifter. I can stop and it will stop. The car is in Overdrive still when this happens. It seems to change from OD to standard from the shifter however. Crazy. Could it be something loose?

I had the same problem and it turned out to be wire chaf.n that wore thru one of the wires drivers side check wires at the back of cyl head for chaf,n mine was a easy cheap fix do it your selfer

[sb2463]

Thanks for all the replies. I had the computer scanned early today. There was a listing on the OD. They tried to simulate and the problem went away. The warning light did not come on again and has not the rest of the day. No more blinking of the OD light either. Might be water related as the has been mucho rain. Trans fluid is also ok. I had changed it at 50K again.

Seems ok now after the re scan.
Thanks
SB.

[bigmerc'03]

the trans wires are chaffed u havent seen the last of the flashing od light i had the same problem read about it on here being a problem look and found the chaffed wires zip tied it and blinking od light went away ...look on the drivers side for your transmission wires bet the chaffed zip tie them to something and let us know how it went

[Stangracer89]

I had the same problem not 2 months ago. OD light just came on and a mile later started flashing. The engine started sputtering and the next day the check engine light came on and all hell broke loose. Ran the 17 codes that came up and they all pointed at the tranny. The next day the weather broke and I popped the hood. Directly under the brake booster is a huge bail of wires on a large connector that SHOULD be firmly attached to a bracket. Mine came off and the wire bundle was resting on the steering shaft. An orange/white wire chafed and broke through. Pulled the neg. on the battery, got out some shrink tube, soldering iron, electric tape and a zip tie. 5 minute fix and all is well. Sure scared me but I got better. I hope your fix is as easy.
Happy motoring!