PT Cruiser L4-2.4L Turbo VIN 8 (2005)
Transmission Control System Relay: Description and Operation
40TE
TRANSMISSION CONTROL RELAY
DESCRIPTION
The transmission control relay is located in the Power Distribution Center (PDC) on the left side of the engine compartment between the brake master
cylinder and the air cleaner assembly (Fig. 356).
OPERATION
The relay is supplied fused B+ voltage, energized by the PCM/TCM, and is used to supply power to the solenoid pack when the transmission is in
normal operating mode. 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 (ignition key turned to the run position or after cranking engine), the PCM/TCM energizes the relay. Prior to this, the PCM/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 PCM/TCM monitors the terminals to verify that the voltage is greater than 3 volts.
