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97 12v no tcc lock I've tried everything please help

3K views 36 replies 6 participants last post by  country_hick 
#1 ·
1997 3500 12v 168k automatic

The torque converter will not lock.
Does go into o/d however
I've tried:

Adjusted tps to 1.0-1.1v
Adjusted tv cable
Checked ground at tps works
Checked brake switch
Checked throttle rod at 5"
Checked AC current at alternator (0volts)
Checked trans relay
Code 1224, not sure what to do
What else is there to check?!?



Please help this is my dd for towing cars
 
#2 ·
I just went through all this with no overdrive. Try this

http://www.tstproducts.com/Torque Converter Lockup Switch.pdf

Also check the bell crank assembly and see if its "loose"



My tps voltage "looked good" as well but was throwing the code. If your lock up works with the switch, you have an external problem, more then likely your tps is the culprit since you have the code.
 
#5 ·
Ok tried the lock up switch and still nothing.

Anyway to put a 1k resistor on the tranny temp sebsor
 
#7 ·
The chart doesn't help. Anyways I tried the 1k resistor on the purple wire for the trans temp and still nothing.
All it did was put it in limp mode
 
#10 ·
I figured the brake switc would be fine if the tail lights stay off and it goes into cruise
 
#11 ·
No, there are three pairs of contacts and for some reason the pair that controls lockup fails most often.
Every thing else can work fine.
I've found the easiest way to check the $12 switch is to just replace it.
Once I found a bent pin not making contact caused by the dealer replacing the switch effecting lockup.
You're sort of plugging it in blind, be careful.
 
#13 ·
Tried the brake light switch still nothing.

I'm going to try the tps I have from a donor truck that o/d worked in.
Is anything going to jump out at me when I take the tps off?
 
#14 ·
So I switched it out and still nothing

Going to try a tps from a previous truck I had that went into o/d.
Is anything going to jump out at me when I take it off?
 
#17 ·
I would look at your electrical wires and connections. A little corrosion in a connector (or a broken or missing wire) can result in no electricity being available to force the electronics to work.
 
#19 ·
And like I had stated before I'm getting a p1224 code. That's why I'm going to try the tps
 
#20 ·
Just to be sure, you read the write up on the tcc lock up switch? when i did mine i originally had the wrong wire tapped and it didnt work. I ended up tapping into the wire right out of the pcm to be sure as i had found another wire the same color on the other side of the engine bay that was not correct.
 
#21 ·
Yea I checked the wire from the plug and used a continuity on the volt meter to double check.
I'm gonna try the pcm swap and rule that out
 
#22 ·
First thing I would be doing is making sure that code 1224 gets cleared. Did the other tps you tried clear the engine code? Did you check those plastic bushings on the bell crank? If those are wore down the tps may not work right as it is attached to that bell crank rod.

Once the code is cleared if you still dont have lock up, and it still wont work with that lock up switch, you probably need that lock up solonoid inside the pan. The lock up and od soloniod share a common posi wire, each has its own ground wire to turn on and off as needed by the pcm. I just watched a guy replace my od/tcc soloniod last weekend, took him an hour to pull the valve body, "refreshen it", install the new electronics and out it back in.

First thing is first, deal with the code.
 
#23 ·
I'm going to clear the codes and go from there.
Ohio hunter, did your od/tcc solenoid throw a code?
 
#24 ·
No code for the od solonoid showed(I dont know if there even is one that would show up). With the scan tool I did originally have two tps codes voltage to high and voltage to low code. My bell crank was really sloppy and loose I rebuilt it like in that video, and replaced the tps at the same time. I had checked the voltage and all the readings but still couldnt get those code's cleared the new tps did that or could of been the bell crank rebuild. I did the same test you did with the tc switch and my tc worked with the switch but no OD. I tried the same test with od and it wouldnt work on the switch. I was sure all my grounds and wires were good, so I figured it had to be the solonoid.
Sounds to me like if you get your tps in order and it still doesnt work it would be that solonoid. Hopefully its just your tps, a couple guys on here helped me trouble shot mine.
 
#26 ·
Here is what I would do next. If you have the code cleared, and have tested your tps, and everything else you did. I would pull the 8 prong plug on top of the transmission. ITs on the drivers side, round plug, clean it up real good, then hit it with grease. Check the wires for any splits, etc. Double check all your connections are good. IF this doesnt work, you can try a pcm reset, unplug the middle pcm connector for a half hour or so. Still no luck try an overdrive switch, same procedure as the tc switch, but instead ground b21, this one controls your overdrive. IF that switch works, most likely its the solonoid for your tc, or something worse internally inside your transmission.
 
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