Power Up Sequence

WARNING: This page is about a different car, the 2006 Mercury Mariner and 2006 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.

The powertrain control module (PCM) must conduct a power-up sequence every time the key is turned from the OFF to the START position. The power-up sequence is carried out only with the electronically controlled continuously variable transaxle (CVT) gear selector in the PARK position. During the power-up sequence the PCM:

initializes and begins CAN communications with the transaxle control module (TCM) and the traction battery control module (TBCM).
checks for TCM error status.
requests the TBCM to close the high voltage contactors.
enables the DC/DC converter.
starts the internal combustion engine.

If the malfunction is detected during the power up sequence, the PCM may initiate LOS mode and store diagnostic trouble codes (DTCs).