DTC B1973: High Power Control Fault: Description

Controlled power relay supplies power to modules during controlled power usage. Whenever PZM is awake and ignition switch has been in LOCK position for 15 minutes or less, high power control output is grounded. After 15 minutes, low power control output is turned on. Low power control output will supply up to 2 amps of current for up to 72 hours. If PZM detects more than 2 amps of current is needed, PZM will wake-up and turn on high power control output.

DTC B1973 will set when high power control voltage does not match that of feedback voltage for 2 seconds. When DTC B1973 is set, PZM will turn low power control output off if ignition is in LOCK, OFF or ACC position. DTC B1973 will clear when PZM does not detect malfunction for one monitoring cycle.