Wiring in a manual switch for TCC on a 4l80e
Wiring in a manual switch for TCC on a 4l80e How would you go about wiring a manual lockup switch on a fully auto 4l80e and not allow the TCC to lock via the pcm on a 2000 camaro with a segment swap and adapter harness? The TCC locks at random times and doesn't seem to care what the tune says. I'd like to experiment with a manual switch and eliminate with the valvebody or the pcm as the culprit. Is the TCC applied when the pcm grounds or applies 12volts? Thanks for the help.
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Joined: Jan 2015
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From: Fort Worth, Texas
The PCM grounds the TCC PWM Solenoid. You will need to turn off all the TCC PWM electrical fault codes along with P1870 & P1860.....If you don't the PCM will command max line pressure & make any results from your test invalid. You can also wire a second "dummy" solenoid on the outside of the trans to keep the PCM happy during your test.
Do use have HP-Tuners or a data capable scan tool?.....This is alot easier than hacking up your wiring & trying to fool the PCM. What is the TCC PWM commanded Duty Cycle when the converter clutch is enabled?
Some "Segments" do not "Take" to the PCM, Did you match the OS numbers?
Do use have HP-Tuners or a data capable scan tool?.....This is alot easier than hacking up your wiring & trying to fool the PCM. What is the TCC PWM commanded Duty Cycle when the converter clutch is enabled?
Some "Segments" do not "Take" to the PCM, Did you match the OS numbers?
The PCM grounds the TCC PWM Solenoid. You will need to turn off all the TCC PWM electrical fault codes along with P1870 & P1860.....If you don't the PCM will command max line pressure & make any results from your test invalid. You can also wire a second "dummy" solenoid on the outside of the trans to keep the PCM happy during your test.
Do use have HP-Tuners or a data capable scan tool?.....This is alot easier than hacking up your wiring & trying to fool the PCM. What is the TCC PWM commanded Duty Cycle when the converter clutch is enabled?
Some "Segments" do not "Take" to the PCM, Did you match the OS numbers?
Do use have HP-Tuners or a data capable scan tool?.....This is alot easier than hacking up your wiring & trying to fool the PCM. What is the TCC PWM commanded Duty Cycle when the converter clutch is enabled?
Some "Segments" do not "Take" to the PCM, Did you match the OS numbers?
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Joined: Jan 2015
Posts: 1,114
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From: Fort Worth, Texas
Its max set to 99 and min set to 98 on the duty cycle across the board. It has a triple disc Circle D. It locks intermittently as soon as the 1-2 shift happens and usually stays locked but will fluctuate around 45-50 when its actually set to lock. Most of the time if you just floor it, the trans downshifts and the TC stays unlocked but if you try and part throttle aggressively it locks prematurely and kills all the fun. It has a new TCC solenoid/harness and a speartech adapter harness. The tune was setup by a very reputable tuner but with all the reading Ive done I have suspected a Segment swap that didn't "take" The OS numbers were matched as far as I know. How do I confirm this and does the issue seem like a segment swap issue?
The TCC PWM Solenoid uses 2nd Clutch Oil to control the TCC Regulator Valve, I would check the external control circuit with a new Solenoid & internal harness already in place.....
Make sure Pin #2 (brown wire) of the Red PCM Connector is wired to Pin "S" of the transmission connector, This is the TCC PWM Solenoid control circuit.
Using a digital volt meter, Hook the red lead to Pin #2, Hook the Black/Common lead to a good ground. I would remove the terminal from the cavity at the PCM, Strip back a 1/4" section of insulation about 2" from the terminal, Slip on a piece of 1/8" heat shrink over the wire, Leave it loose for now....You can heat it in place after the diagnostics.
The objective is to watch line voltage on the circuit.......The "High's"...Around 12vdc when the solenoid is commanded "off/venting" (Un-locked).
And the "Low's"....Zero Volts when the solenoid is commanded "on/closed" (TCC locked)
The variable here is the possibility that the circuit is getting dragged low by a intermittent short to ground in the harness between the trans & PCM.
Hey Im sorry Ive been out of town picking up a car from Arkansas. I do have HPtuners and do have the tune for this car. Ill send you a PM. The next time I'm around the car we will try and diagnose the wiring.
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Joined: Jan 2015
Posts: 1,114
Likes: 33
From: Fort Worth, Texas
I was finally able to view your tune.
Set all the "Release TPS" tables to 100% across the board, The tabs are highlighted in red, I have never seen these tables....Stock or Tuned have the values you have in your tune.
Changing certain tables on certain PCM's can cause wacky things to happen, To tell you the truth.......I don't really know what the TPS Release tables do that can't be done in the Apply/Release Tables.
I have my Apply/Release tables set to not lock the TCC above 50% TPS & Will unlock the TCC if I exceed 50% TPS even though my TPS Release Tables are maxed out.
Your Normal TPS Release Table.....
My Normal TPS Release Table.....
Set all the "Release TPS" tables to 100% across the board, The tabs are highlighted in red, I have never seen these tables....Stock or Tuned have the values you have in your tune.
Changing certain tables on certain PCM's can cause wacky things to happen, To tell you the truth.......I don't really know what the TPS Release tables do that can't be done in the Apply/Release Tables.
I have my Apply/Release tables set to not lock the TCC above 50% TPS & Will unlock the TCC if I exceed 50% TPS even though my TPS Release Tables are maxed out.
Your Normal TPS Release Table.....
My Normal TPS Release Table.....
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TECH Fanatic
Joined: Jan 2015
Posts: 1,114
Likes: 33
From: Fort Worth, Texas
If it still locks/stays locked under heavy throttle, Max out the Apply & Release values above the TPS% value that you want it to Unlock at.
I wanted mine to Unlock at any TPS over 50%......And only lock in 4th gear.
Yours will stay locked til 3/4 throttle in 4th gear.
I wanted mine to Unlock at any TPS over 50%......And only lock in 4th gear.
Yours will stay locked til 3/4 throttle in 4th gear.
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