AT Oil Temp Light (1 Viewer)

[Flyingvp]

I have done several searches, but not come up with a matching scenario. Our 1988 FJ62 has the AT Oil Temp light on all the time. The light came on after changing the transmission oil filter. I had removed the transmission to replace the rear main seal. While the transmission was out I washed off the dirt and grime, let it dry, and then replaced the filter. After putting things back together, the transmission performs as it did before. The only difference is the AT Oil Temp light is on all the time. For the first several days the light would come on several minutes after start up. My daughter drives it to school, we live about a mile away. It is winter in Idaho so, cold mornings and she warms it up before she leaves. The oil is not hot in that amount of time. I did mess with the sensor connector a little bit, made sure it was dry and clean. Now the light comes on right at start up and stays on until the truck is shut off.

Is it just the sensor or could it be something else? I do have a sensor on order, but I'm wondering if it could be something else.

Thanks for any information or help you can give.

 

[OSS]

Disconnect the sensor wire and see what happens. Since you fiddled with it — that seems like a good place to start.

 

[Flyingvp]

I will give that a try. Thanks.

 

[Michael Hanson]

Hi, With all our cruisers I’ve found the lights to be very dependable. Heat or fluid blockage could be a problem. How do you know the fluid is not to hot ? Check also for a wire that is corroded or rubbing on metal some where maybe under the shifter. Mike

 

[Randy88FJ62]

I swapped my A440F years ago and the light stayed on. I was lazy and never looked into it. You are on the right path with the sensor and wiring. If you don't have the A440F service manual let me know and I can give you a dropbox link.

 

[Flyingvp]

Hi, With all our cruisers I’ve found the lights to be very dependable. Heat or fluid blockage could be a problem. How do you know the fluid is not to hot ? Check also for a wire that is corroded or rubbing on metal some where maybe under the shifter. Mike

I will check the wiring like you suggest. I say the fluid is not hot because I pulled the transmission dipstick several times after driving and the fluid barely feels warm. Maybe that is not the best way to check. Thanks for the help.

 

[Flyingvp]

I swapped my A440F years ago and the light stayed on. I was lazy and never looked into it. You are on the right path with the sensor and wiring. If you don't have the A440F service manual let me know and I can give you a dropbox link.

I do not have an A440F service manual. That would be great. Thanks.

 

[Randy88FJ62]

I do not have an A440F service manual. That would be great. Thanks.

pm me your email

 

[pithicus]

I swapped my A440F years ago and the light stayed on

Same. Except mine stays on for 5 mins, then flickers on and off for 10 mins then goes off.