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Electrical Power Management Description and Operation

Electrical Power Management Description and Operation

Electrical Power Management

The electrical power management is used to monitor and control the charging system and alert the driver of possible problems within the charging system. The electrical power management system makes the most efficient use of the generator output, improves the battery state of charge, extends battery life.

The "idle boost" operation is a means of improving generator performance during a low voltage or low battery state-of-charge condition.

Idle boost is activated in incremental steps, idle boost 1 must be active before idle boost 2 can be active. The criteria used by the body control module (BCM) to regulate electrical power management are outlined below:

Operation Battery Temperature Calculation Battery Voltage Calculation Amp-hour Calculation Action Taken
Idle Boost 1 Start

Less Than -15°C (5°F)

Less Than 13 V

-

First level Idle boost requested

Idle Boost 1 Start

-

-

Battery has a net loss greater than 0.6 AH

First level Idle boost requested

Idle Boost 1 Start

-

Less Than 11 V

-

First level Idle boost requested

Idle Boost 1 End

Greater Than -15°C (5°F)

Greater Than 12 V

Battery has a net loss less than 0.2 AH

First level Idle boost request cancelled

Idle Boost 2 Start

-

Less Than 11 V

-

Second level Idle boost requested

Idle Boost 2 End

-

Greater Than 12 V

Battery has a net loss less than 0.8 AH

Second level Idle boost request cancelled

Idle Boost 3 Start

-

-

Battery has a net loss of 10 AH

Third level Idle boost requested

Idle Boost 3 Start

-

Less Than 11 V

-

Third level Idle boost requested

Idle Boost 3 End

-

Greater Than 12 V

Battery has a net loss of less than 6 AH

Third level Idle boost request cancelled