Transmission Control Module (TCM)
The TCM determines shift points and torque converter lock-up based on input signals received from throttle position sensor, park/neutral position switch, speed sensor and brake switch. The TCM controls transmission shift points and torque converter lock-up by operating electric solenoids mounted on the valve body.
The TCM contains a self-diagnostic system used for determining an electronic component failure. The TCM self-diagnostic system will store a diagnostic trouble code in the TCM memory if certain electronic problems exist. If electronic problem goes away, diagnostic trouble code will be erased from TCM memory after ignition has been cycled approximately 75 times.
Diagnostic Trouble Codes (DTCs) can be retrieved using a Diagnostic Readout Box (DRB). After repairing an electrical system problem, stored diagnostic trouble code must be cleared from TCM memory.
The TCM is located behind right side of instrument panel. See Fig 1 .