Idle Boost Functions
The BCM sends a serial data request to the ECM to increase the idle speed. The ECM then adjusts the idle speed by using a special program and idle speed ramp calculations in order to prevent driveability and safety concerns. The idle speed boost and cancel function will vary from vehicle to vehicle and from one moment to another on the same vehicle. This happens because the ECM responds to changes in the inputs from the sensors used to control the powertrain.
Load Shed System Description and Operation
| 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. |
| 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 40 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 are not affected. The indicators and timers are controlled by the BCM. 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. Charge indicator is illuminated. 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 40 ignition switch cycles with no repeated Load-Shed 2 actions or with a battery disconnection. |