Tranny lock - up.
Thread Starter
Melting Slicks
Joined: Oct 2000
Posts: 3,010
Likes: 1
From: Sweden/Stockholm
Tranny lock - up.
As some of you know I have ( i think ) probleme with my lock-up. It doesnt engage like it should. So I have some questions about this, I hope you can help me with some questions..
Is there som fuse for the lock-up function? In my hanyes manual it say that there sould be a "GA-TRANS fuse" in the fuse box. But I cant find it.
Could it be that the preowner has installed a aftermarket chip that disable the lock.up? And why would you whant that?
Can I hurt the tranny if I run it like this, without the lock.up?
I know my tranny has been changed somtime, could it be badly installed, so the lock-up doesnt work ?
best regards..
//Devil
Is there som fuse for the lock-up function? In my hanyes manual it say that there sould be a "GA-TRANS fuse" in the fuse box. But I cant find it.
Could it be that the preowner has installed a aftermarket chip that disable the lock.up? And why would you whant that?
Can I hurt the tranny if I run it like this, without the lock.up?
I know my tranny has been changed somtime, could it be badly installed, so the lock-up doesnt work ?
best regards..
//Devil
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: Tranny lock - up. (devilfish)
On my '88 the TCC lockup fuse is labeled "GAUGES FUSE"; here's the setup:
From there the power passes through the "TCC/CRUISE BRAKE SWITCH". Opens to disable lockup when the brake pedal is depressed. (check this one)
From there the power goes to the tranmsmission solenoid. (opens on normal downshift from 4th to 3rd)
The lockup command signal (ground) comes from the ECM and can be accessed at ALDL pin "F". Connect ALDL pins "F" & "A" to force the TCC to lockup, except in 1st gear. Or connect a diagnostic "lamp" (a mini LED in series with a 2.2kOhm resister works) across pins "F" & "A"; the "lamp" will be light when the TCC is NOT locked up.
Connect a switch across ALDL pins "F" and "A" and see if you can force the TCC to lockup by closing the switch at highway speeds. Connecting the test "lamp" across those terminals will tell you if the ECM is commanding the TCC to lockup when in 4th gear.
I've heard that if the TCC isn't locked under normal operation it can cause excessive heating of the fluid. Of course fuel economy will suffer too.
From there the power passes through the "TCC/CRUISE BRAKE SWITCH". Opens to disable lockup when the brake pedal is depressed. (check this one)
From there the power goes to the tranmsmission solenoid. (opens on normal downshift from 4th to 3rd)
The lockup command signal (ground) comes from the ECM and can be accessed at ALDL pin "F". Connect ALDL pins "F" & "A" to force the TCC to lockup, except in 1st gear. Or connect a diagnostic "lamp" (a mini LED in series with a 2.2kOhm resister works) across pins "F" & "A"; the "lamp" will be light when the TCC is NOT locked up.
Connect a switch across ALDL pins "F" and "A" and see if you can force the TCC to lockup by closing the switch at highway speeds. Connecting the test "lamp" across those terminals will tell you if the ECM is commanding the TCC to lockup when in 4th gear.
I've heard that if the TCC isn't locked under normal operation it can cause excessive heating of the fluid. Of course fuel economy will suffer too.
