What are the TCC used for on the pcm?
03-27-2013, 02:35 PM
#1
What are the TCC used for on the pcm? Do I need them?
Car is 98 a4 ls1.
I am trying to delete any unneeded wires. Car is race only
Wires in question are PCM:
77 PPL TCC/Brake Switch Signal
32 TAN/BLK TCC Enable Control
33 BRN TCC (PWM) Solenoid Valve Control
Car is 98 a4 ls1.
I am trying to delete any unneeded wires. Car is race only
Wires in question are PCM:
77 PPL TCC/Brake Switch Signal
32 TAN/BLK TCC Enable Control
33 BRN TCC (PWM) Solenoid Valve Control
03-28-2013, 08:53 AM
#7
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Like he stated, if you wish to use lockup you will need that wire. The brake switch is a normally-closed switch that supplies battery voltage on circuit 420 to the PCM. Applying the brake pedal opens the switch, interrupting voltage to the PCM. When the brake pedal is released, the PCM receives a constant voltage signal. If the PCM receives a zero voltage signal at the brake switch input, and the Torque Converter Clutch (TCC) is engaged, the PCM de-energizes the Torque Converter Clutch Solenoid Valv. The PCM disregards the brake switch input for TCC scheduling if there is a brake switch circuit fault. In the end, it will probably act weird when slowing down since it has no way to determine your foot is on the pedal. I recommend researching a circuit before cutting the wires or else were going to have 20+ other "I cut this and now it doesn't work" threads.
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03-28-2013, 10:59 AM
#8
Like he stated, if you wish to use lockup you will need that wire. The brake switch is a normally-closed switch that supplies battery voltage on circuit 420 to the PCM. Applying the brake pedal opens the switch, interrupting voltage to the PCM. When the brake pedal is released, the PCM receives a constant voltage signal. If the PCM receives a zero voltage signal at the brake switch input, and the Torque Converter Clutch (TCC) is engaged, the PCM de-energizes the Torque Converter Clutch Solenoid Valv. The PCM disregards the brake switch input for TCC scheduling if there is a brake switch circuit fault. In the end, it will probably act weird when slowing down since it has no way to determine your foot is on the pedal. I recommend researching a circuit before cutting the wires or else were going to have 20+ other "I cut this and now it doesn't work" threads.
04-04-2013, 09:11 AM
#9
My TCC switch on the pedal has never worked properly. What it causes (based on reading how other peoples cars react) is that when you lift off the throttle the converter automatically unlocks based on throttle percentage being too low.
People on here in stock cars have said the converter stays locked at certain speeds with no throttle until the speed drops too low or the brake is pressed. If this is the case the downsides would be slight decrease in fuel mileage and more wear on the lock up clutch since it would be going off/on a lot more often on highway driving.
If anything I said is incorrect, feel free to correct me. But my car works fine with the switch malfunctioning...just gets irritating on the highway due to frequent lock/unlock at certain speeds because I don't need much throttle to maintain that speed. Only an issue in traffic really.
People on here in stock cars have said the converter stays locked at certain speeds with no throttle until the speed drops too low or the brake is pressed. If this is the case the downsides would be slight decrease in fuel mileage and more wear on the lock up clutch since it would be going off/on a lot more often on highway driving.
If anything I said is incorrect, feel free to correct me. But my car works fine with the switch malfunctioning...just gets irritating on the highway due to frequent lock/unlock at certain speeds because I don't need much throttle to maintain that speed. Only an issue in traffic really.
04-08-2013, 08:46 AM
#10
My TCC switch on the pedal has never worked properly. What it causes (based on reading how other peoples cars react) is that when you lift off the throttle the converter automatically unlocks based on throttle percentage being too low.
People on here in stock cars have said the converter stays locked at certain speeds with no throttle until the speed drops too low or the brake is pressed. If this is the case the downsides would be slight decrease in fuel mileage and more wear on the lock up clutch since it would be going off/on a lot more often on highway driving.
If anything I said is incorrect, feel free to correct me. But my car works fine with the switch malfunctioning...just gets irritating on the highway due to frequent lock/unlock at certain speeds because I don't need much throttle to maintain that speed. Only an issue in traffic really.
People on here in stock cars have said the converter stays locked at certain speeds with no throttle until the speed drops too low or the brake is pressed. If this is the case the downsides would be slight decrease in fuel mileage and more wear on the lock up clutch since it would be going off/on a lot more often on highway driving.
If anything I said is incorrect, feel free to correct me. But my car works fine with the switch malfunctioning...just gets irritating on the highway due to frequent lock/unlock at certain speeds because I don't need much throttle to maintain that speed. Only an issue in traffic really.
Boy it sure is nice to have it locked up on decel, it gives nice engine braking, especially when it goes into DFCO.
