Nitro 2WD V6-4.0L (2007)
Transmission Control System Relay: Description and Operation
Operation
OPERATION
NOTE: Due to different power control configurations, the Transmission Control Relay (if equipped) may be referred to as a PCM relay.
When the relay is "off", no power is supplied to the solenoid pack and the transmission is in "limp-in" mode. After a controller reset, the TCM energizes
the relay. Prior to this, the TCM verifies that the contacts are open by checking for no voltage at the switched battery terminals. After this is verified, the
voltage at the solenoid pack pressure switches is checked. After the relay is energized, the TCM monitors the terminals to verify that the voltage is
greater than 3 volts.
