Ive had the governor switches replaced, but heres the problem. when its cold like 25 or below when you crank it in the mornings the od light stays on and the trans is stuck in third after you drive it about 10 miles and cut the vehicle of the light goes off. It wont come on every morning. Ive also noticed that if i leave the heat selecter switch on it does it all the time, but if the selector switch is in the off position it dont do it as much, sounds crazy i know but it semms to be involved. Its a 95 jeep grand cherokee with a 4.0 and 4 wheel drive. Im new here and i have searched the forums but havnt found anything, im running out of options so thanks for any help.
i doubt that the heater control has anything to do with the overdrive circuit. The od switch goes directly to the PCM. The switch is a momentary type, hit it once, it turns off the over drive seleniod & turns on the lamp. Hit it again tells PCM to re-energize the selenoid & turns off the lamp. I would suspect the switch. Pull the switch & check for continuity it should only read when pressed. I had a car that when it got extremely cold the horn would turn on. Steering wheel horn switch pad was bad.
ive tried warming up for 15 or 20 mjnutes but it didnt help either, my tranny mechanic said the tranny fine, hes one of the best in my area. i was wondering if it could be in iginition switch. Its gremlin, has to be.
warming up the engine doesn't do anything for the transmission, which is what i was saying needed to warm up before functioning right. i think you have a bad gov pressure/temperature sensor(same unit).
try warming up the jeep while the tranny is in neutral and see if that does anything for you(the tranny won't circulate fluid unless it is in a drive gear or neutral).
'97 zj 5.2, some stuff, some other suff, and some things that even work sometimes.
I believe it goes by coolant temperature though before shifting into 4th. It gets real cold here as well and i notice this all of the time but the light never comes on, it will just act like the OD is off until the coolant reaches a certain temp. I am guessing around 120ish. And the OP does not have 1-2 shifts, only 3 until warm.
tranny guy pulled codes today it had for gov sol, torq convert circuit, od circuit. I think im haven a problem with the power supply feeding these switches but i dont know where the supply comes from like ign switch, pcm, or tcm.