Overdrive Issue

Vehicle: 2001 Tacoma 4x4, Auto, V6
Problem: The overdrive does not engage
Details: The o/d button appears to work in the dash(light on and off) but has no effect on the gear. No check engine light. OBD2 monitors coolant temp sensor works properly. Truck shifts through all other gears seemingly as it should. Have done the manual shift test and it works as it should, L-1st,2-3rd,D-4th/o/d
Running 3100 rpms at 65mph
Solution:?

 

check your brake light switch first.

 

Brake lights cut on and off as they should.

 

Update: Trans shop says that the trans is mechanically sound. Torque converter(TC) will not lock up either. The ECU is not telling the trans to go into OD or the TC to lock-up.

 

Anyone? I've replaced the computer and have the same problem.

 

First off, I am NOT a mechanic. But I use my switch religiously and tried to think what I would do in your shoes. Wonder if it is a wiring issue. May need to check the wiring coming from the button to the computer? Was thinking if the computer is new and the switch is working, then it may be wiring or the switch itself isn't making proper contact? Idk
My 2 cents

 

This could happen if the trans temp is too low, or the temp sensor is broken and reading low

 

Mech said the trans was hot enough @Speedytech7 and I have tested the switch and its wiring @Yocatoma

 

Bump

 

Bump