[Deib]

How do I trouble shoot the TC circuit without a scan tool?

I know there is the purple wire with yellow stripe, it should lock up if I ground that.

So where does it get it's power? Is there more than one wire that controls or supplies power to the TC convertor.

I am looking for ways to test the TC circuit inside the tranny so I can figure out if my problem is internal or external.

 

[STurbo90]

The power going into the transmission is the same power source as the pcm, comes from the pcm relay.

The same power wire feeds the pressure control, shift 1, TCC, shift 2, coast clutch, solenoids.

 

[danjreed]

http://rides.webshots.com/photo/2649993560096577034wsGban

All the power to the transmission is on the red wire. If it shifts at all, that means it has power on that wire.
To test the TCC solenoid electrically, note the position of the RED wire and the PPL/YEL wire in the connector. Then pull the connector and check the resistance between those two terminals. Or, cut the PPL/YEL wire and check the current thru it when the PCM end of the wire is grounded. If you have high resistance or low current, the solenoid or internal wiring might be bad.

 

[Deib]

Bringing this back since I finally got a little time to mess with it.

So I grounded the purple and yellow wire. With the truck running. I thought I read somewhere that even in park it should try to engage the TQ, is that right?

When I grounded it, nothing happened. I put a test light on it, and I have voltage coming out of the transmission in the purple/yellow wire, so that at least means I have continuity through the solenoid pack right?

I thought I had a astg manual for it, but I can't find it after the move.
Is that the only thing in that circuit?
Should I just buy a solenoid and put it in?

Thanks

 

[frmrdieseldriver]

its a pretty expensive gamble. I payed a 108.00 for mine rebuilt, or whatever you want to call it, just not new. but, I had mine scanned to confirm it was bad. my symptoms were, it shifted fine until it warmed up. bad solenoids obviously don't work as well as they should when hot. hope this helps

 

[Mark Kovalsky]

If you have the right wire and everything in the torque converter lockup system works, grounding the wire in park will lock the torque converter.

Locking the torque converter in park causes absolutely nothing to happen!

If you were to ground the wire with the trans in drive AND YOUR FOOT HARD ON THE BRAKE it will stall the engine if everything is working.

 

[Deib]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Mark Kovalsky</div><div class="ubbcode-body">
Locking the torque converter in park causes absolutely nothing to happen!

</div></div>

Cool, that will help. So I was testing it wrong.

There may be hope yet. If the thing tried to lock up, which I hope it does, then I know my problem is someplace else, not in the TC, or solenoids.

 

[danjreed]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Deib</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Mark Kovalsky</div><div class="ubbcode-body">
Locking the torque converter in park causes absolutely nothing to happen!

</div></div>

Cool, that will help. So I was testing it wrong.

There may be hope yet. If the thing tried to lock up, which I hope it does, then I know my problem is someplace else, not in the TC, or solenoids. </div></div>

I wouldn't use the brake method. Too much chance of the brakes slipping if you don't guess enough force on the pedal. Safety stands/blocks of wood are a better bet. Make sure you're not in 4x4.
Then test.

 

[Racer_X]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Deib</div><div class="ubbcode-body">How do I trouble shoot the TC circuit without a scan tool?

I know there is the purple wire with yellow stripe, it should lock up if I ground that.

So where does it get it's power? Is there more than one wire that controls or supplies power to the TC convertor.

I am looking for ways to test the TC circuit inside the tranny so I can figure out if my problem is internal or external. </div></div>

<span style='font-size: 14pt'>Just wondering what the problem is--no TCC lock? While lockup is PCM controlled, the pump valve is what allows lock and unlock of the converter. If the clutch has worn out it won't lock either. Just like the clutch in a manual transmission, the clutch surface will wear out. It's possible for all to work as it should, but just be worn.</span>

 

[Deib]

Well just an update in case someone else has this problem.
I had the wife, (yes I trust her with my life) put the truck in gear and foot on the brake.
I grounded the purple wire with yellow stripe, and the truck died.
That circuit is working fine.
With just the key on, engine not running you can ground the purple wire and hear the solenoid click.

What has happened is the Gear vendor actually breaks the purple wire, it comes from the tranny, through the GV control module and back to PCM? or where ever it goes.
The GV module apparently is bad, and burn open? or relay is stuck open not allowing the circuit to continue, even though it is switched off, and power removed.
Bypassed the GV controls, unhooked the batteries for a couple minutes and all is well.
When I installed the GV I bought all new updated stuff from GV and it worked perfectly for years. All the sudden one day it stopped working, and it has been one problem after another with it since.
I think it is a great unit, but we are making our own control module.

 

[danjreed]

Well, the GV unit changes everything. I didn't see it in your sig. Yes, they will split several signals so you don't really know what is going on.
Good luck on the custom controller.