Test M: The Charging System Warning Indicator Is Never/Always On

PINPOINT TEST M: THE CHARGING SYSTEM WARNING INDICATOR IS NEVER/ALWAYS ON

Normal Operation
The charging system indicator is controlled by the instrument cluster (IC) based upon data received from the PCM over the high speed controller area network (HS-CAN) communication bus.

If the charging system message is missing or invalid for less than 5 seconds, the charging system indicator remains in the last indication mode (on or off). If the charging system message is missing for more than 5 seconds, the instrument cluster (IC) sets DTC U0101 in continuous memory and defaults the charging system warning indicator on. If the charging data received is deemed invalid by the instrument cluster (IC) for 5 seconds or longer, the instrument cluster (IC) sets DTC U2023 and defaults the charging system warning indicator on.

NOTE: If DTC U0101 is set in the instrument cluster (IC), other observable symptoms may be an inoperative speedometer, tachometer or odometer.

This pinpoint test is intended to diagnose the following:
- Charging system concern
- PCM
- Instrument cluster (IC)

M1:

M1-M6: