Chart 2 Blower On All the Time
CIRCUIT DESCRIPTION
The airflow is controlled by modulating the commanded blower voltage which varies the blower speed. The blower is a function of the program number when it is under automatic control with adjustments being made based on vehicle speed, coolant temperature, and Sun Load Sensor load. There are special cases which may override the normal operation of the blower such as to limit snow ingestion, purge air ducts, cool the instrument panel cluster, or enhance heater warm-up performance.
TEST DESCRIPTION
If the blower is inoperative in normal operating procedures, but operates properly in override, the Instrument Panel Cluster (IPC) or data line between the IPC and Air Conditioning Programmer (ACM) is suspect.