GM Service Manual Online
For 1990-2009 cars only

Load Shed Level

Affected Systems

Action Taken

Load-Shed Level 0

No systems affected

Normal operation

Load-Shed Level 1

Heated Outside Rear View Mirrors, Heated Rear Window / Rear Window Defrost, Heated Seats

Cycled at 80% duty cycle, OFF for 4 of every 20 second cycle. Indicator and timer not affected.

Front Automatic HVAC

Reduce blower speed to 80% of current setting if the HVAC is not in the Defrost mode. The HVAC controller uses a ramping program to make the change invisible to the operator. No action is taken if the HVAC system is in Defrost.

Rear Automatic HVAC

Turn OFF blower. The operator must turn ON system when load-shed level is exited. System will not respond to operator input until current load-shed level is exited.

Message Center, Instrument Cluster

No messages or indicators are displayed. Data (DPID) indicating that the Load-Shed 1 was entered is stored and may be accessed with a scan tool. DPID will reset after 50 ignition switch cycles with no repeated load-shed 1 action or with a battery disconnection.

Load-Shed Level 2

Heated Outside Rear View Mirrors, Heated Rear Window / Rear Window Defrost, Heated Seats

Turned OFF. Indicator and timer also turned OFF. The operator must turn ON system when load-shed level is exited. System will not respond to operator input until current load-shed level is exited. This system will respond to only one Load-Shed Level 2 command per ignition switch cycle.

Front Automatic HVAC

Blower turned OFF if the HVAC system is not in the Defrost mode. No action is taken if the HVAC system is in the Defrost mode. Operator may over-ride by manually turning the blower ON. This system will respond to only one Load-Shed 2 command per ignition switch cycle.

Rear Automatic HVAC

Rear HVAC blower remains OFF. The operator must turn ON system when load-shed level is exited. System will not respond to operator input until current load-shed level is exited. This system will respond to only one Load-Shed Level 2 command per ignition switch cycle.

Message Center, Instrument Cluster

"Battery Saver Action" message is displayed. Battery / Charging System Failure icon is illuminated. Chime may be activated constantly until the load-shed level is exited. Data (DPID) indicating that the Load-Shed Level 2 was entered is stored and may be accessed with a scan tool. DPID will reset after 50 ignition switch cycles with no repeated Load-Shed 2 actions or with a battery disconnection.