I hoped I might get more replies here than in tranny section. Anyway, tranny builder says he checked the lock up solenoid a couple months ago when he rebuilt the transmission (and it was good) so I wanted to check everything else before I get to the solenoid. Transmission was just rebuilt a few months ago. Before the rebuild, TC had locked fine, then it would only lock after 12 miles of highway driving, then it wouldn't lock at all. Sent the TC to Dusty who rebuilt it and said the clutches were fried. So now, in a newly rebuilt transmission, it still does not lock up. I tried jumping the two ports (A and F I believe, upper left and upper right) in the ALDL but nothing happened at 50 mph. So I put my test light on the wires from the ALDL and found that the light comes on when I accelerate and goes off if I take my foot off the gas. Does this even in slow city driving. If I keep my foot on the gas (light on) and I tap the brake the light goes off (like it should, right?). Also, scan tool shows it is locked at about 50 mph so the signal is getting to the ALDL. Does this rule out any issues with the plunger switches by the brake pedal? My next plan is to run a couple jumper wires from the 4 prong plug on the side of the transmission into the passenger compartment and seeing if my test light lights up by touching the purple hot wire and black wire, going 50 mph. Any other suggestions? So if the power and ground functions correctly in the 4 prong connector, would it then have to be a bad lock up solenoid? Thanks!
Torque Converter not locking
- Thread starter GNRick
- Start date
Sounds like you've did the troubleshooting correctly. The ground side for the TCC comes from the pressure switch then runs through the ECM... which you saw with the ALDL connector and scan tool. The hot side is the brake pedal and the purple wire will lose power when pushing the brake pedal.
Have you listened to see if you can hear the TCC with KOEO and tapping the brake pedal with the DS door open?
If you're going to run jumpers inside the car from the tranny, wire up the TCC to a cig lighter adapter. Get up to cruise speed and plug it in. (stick a light on the jumper so you know it's hot). If it doesn't lock, you know it's inside the tranny.
Have you listened to see if you can hear the TCC with KOEO and tapping the brake pedal with the DS door open?
If you're going to run jumpers inside the car from the tranny, wire up the TCC to a cig lighter adapter. Get up to cruise speed and plug it in. (stick a light on the jumper so you know it's hot). If it doesn't lock, you know it's inside the tranny.
So when the circuit is made, the cig. lighter will engage? Wouldn't it just be easier to see if the test light comes on? Although your method is kind of cool. Do I understand that right? Also, if I tap the brake, what kind of sound should I hear? Thanks Earl.
I was talking about powering the plug on the tranny using the cig lighter. The light was to make sure power was in the jumper as we have rusty crappy lighters from the 80's 
Once the fuel pump and powermaster shut up you can hear the TCC clicking when you tap the brake pedal (if it's working that is). Make sure to ground the TCC ALDL or flip the lock up switch in the ashtray.
Have you got another lock up car you can try it with to hear the clicky clicky sound?
Once the fuel pump and powermaster shut up you can hear the TCC clicking when you tap the brake pedal (if it's working that is). Make sure to ground the TCC ALDL or flip the lock up switch in the ashtray.
Have you got another lock up car you can try it with to hear the clicky clicky sound?
The TCC switch is a fluid solenoid. The click you hear is the TCC opening up a fluid path into the TC to actuate the clutch. Obviously, since the engine is running there's no fluid pressure but you did verify you have working power on both sides of the electrical circuit.
Dumb question but how can you hear the TCC with the car stopped? I thought stock setup was in 3rd and 4th only and had to be above about 45MPH VSS. Once it locks at speed, tapping the brake pedal with your left foot you should hear the engine gain 50 RPM and feel the lock/ unlock pitch change at fixed throttle. Am I missing something?
