Automatic Transmission/Transaxle: Description and Operation

Circuit Description
The Transaxle Control Module (TCM) provides precise gear shift timing and torque converter lock-up by controlling the operation of the automatic transaxle solenoid valves (Low & reverse solenoid valve damper clutch control solenoid valve, over-driver solenoid valve, 2nd solenoid valve and under-driver solenoid valve).

The TCM operates these solenoid valves based on input signals from the various sensors (for instance, pulse generator A, B). The transaxle control module has a built-in self diagnostic feature.