SUBJECT:
FLASH: Electric Vehicle Control Unit (EVCU) System Enhancements
OVERVIEW:
This bulletin involves updating the software in the EVCU.
SYMPTOM/CONDITION:
A small number of customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon
further investigation, the technician may find the following Diagnostic Trouble Code (DTC) set in
the EVCU memory:
• P1A21-00 - HV Battery Contactor Control Sequence Incorrect. In addition the customer may
notice one of the following conditions:
• When an Electric Vehicle Supply Equipment (EVSE) is plugged in approximately 17 seconds after
key off, the vehicle will not charge and will not power down. This could lead to potential 12V
battery drain after prolonged period of time.
• When the battery temperature is below -30°C (-22°F) and above 50°C (122°F), the thermal
system does not function.
• When a Level 1 EVSE is plugged in, the displayed charge time estimation for Level 2 is over
estimated.
The following improvements/enhancements are also included in this software release:
• Improved shift strategy involving shift lever position.
