I have 46rh that i just put in my 85 D150.. Do i have to hook up the OD/LU?

 

You don't actually 'have to'...... and so far as I know, the 85 PCM has no provisions for controlling it in any event....... Somewhere around here, there is a thread on how to make O/D and lockup work without PCM control...... Search should turn it up.

 

yea i read it but i want to test drive truck nd get all the kinks worked out then i hook up the OD/LU

 

You can drive it without it hooked up. Won't cause any problems.

 

do you know what kind of rear axle an 88 D250 has?

 

https://transmissioncenter.net/shop/...iring-diagram/

 

I realize this is a two year old post but I hope you are still around. My 1992 has a 3 speed auto. It has a constant maintenance light and the code is "Overdrive Transmission Solenoid". Since it is not an overdrive trans I've ignored the light. However, after reading your post I am intrigued by the thought that the lock-up torque converter might not be locking and that is what is causing the fault. What locks the converter? Is it a solenoid?

 

has the trans in your truck been changed? TCC has it's own codes...... and the PCM *should* be aware of that.

 

Trans never removed. I replaced the solenoid this past weekend but I can't tell that anything has changed. I don't have the reader required to reset the code so I guess I'll have to wait until 50 startups to see if it worked. It really doesn't drive any different than before. The code is 45 which says either open or shorted overdrive solenoid circuit. I checked resistance from wire to frame and got 20 ohms. That is neither short nor open. However, I haven't found anything that says what it should be. I also haven't found any fuse nor relay for this circuit. It is a single wire connection, blue insulation with a white stripe. I disconnected the battery in hopes it would reset the code but that didn't work.