Torque Converter Clutch (TCC)
See MISCELLANEOUS PCM/VCM CONTROLS .
Torque Converter Clutch
See MISCELLANEOUS PCM/VCM CONTROLS .
The transmission/transaxle Torque Converter Clutch (TCC) eliminates power loss of torque converter stage when vehicle is in a cruise condition, allowing driver the convenience of an automatic transmission while providing the fuel economy of a manual transmission. Fused battery ignition is supplied to TCC solenoid through a brake switch.
On some models, 2nd, 3rd and 4th gear hydraulic apply switches (located within transmission) may also be in series with solenoid power or ground circuit. On other models, switch status may only be monitored by PCM, without sharing power or ground with TCC solenoid. For wiring reference, see appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.
The TCC engages when vehicle is moving faster than a pre-calibrated speed, engine is at normal operating temperature, throttle position sensor output is not changing (indicating a steady road speed) and transmission 3rd gear or high gear switch (if equipped) and brake switch are closed.
When vehicle speed is great enough (about 20-45 MPH as indicated by the vehicle speed sensor), PCM energizes TCC solenoid mounted in transmission, allowing torque converter to directly connect engine to the transmission. When operating conditions indicate transmission should operate as normal, TCC solenoid is de-energized, allowing transmission to return to normal automatic operation. Since power for the TCC solenoid is delivered through the brake switch, transmission also returns to normal automatic operation when brake pedal is depressed. To check function of TCC system, perform functional check of system. See MISCELLANEOUS PCM/VCM CONTROLS in appropriate SYSTEM & COMPONENT TESTING article.