Suzuki XL7 2007 Service Manual page 898

1J-5 Charging System:
Battery Sulfation Mode
The BCM will enter this mode when the interpreted
generator output voltage is less than 13.2 volts for 45
minutes.When this condition exists the BCM will enter
Charge Mode for 2-3 minutes. The BCM will then
determine which mode to enter depending on voltage
requirements.
Charge Mode
The BCM will enter Charge Mode when ever one of the
following conditions are met.
• The wipers are ON for than 3 seconds.
• GMLAN (Climate Control Voltage Boost Mode
Request) is true, as sensed by the HVAC control
head. High speed cooling fan, rear defogger and
HVAC high speed blower operation can cause the
BCM to enter the Charge Mode.
• The estimated battery temperature is less than 0°C
(32°F).
• Battery State of Charge is less than 80%.
• Vehicle Speed is greater than 145 kph (90MPH)
• Current Sensor Fault Exists
• System Voltage was determined to be below 12.56
Volts
When any one of these conditions is met, the system will
set targeted generator output voltage to a charging
voltage between 13.9V and 15.5V, depending on the
battery state of charge and estimated battery
temperature.
Fuel Economy Mode
The BCM will enter Fuel Economy Mode when the
estimated battery temperature is at least 0°C (32°F) but
less than or equal to 80°C (176°F), the calculated battery
current is less than 15 ampers and greater than − 8
ampers, and the battery SOC is greater than or equal to
80%.It's targeted generator output voltage is the open
circuit voltage of the battery and can be between 12.5
and 13. 1 volts. The BCM will exit this mode and enter
Charge Mode when any of the conditions described
above are present.
Headlamp Mode
The BCM will enter Headlamp Mode when ever the
headlamps are ON (high or low beams). Voltage will be
regulated between 13.9 and 14.5 volts
Start Up Mode
When the engine is started the BCM sets a targeted
generator output voltage of 14.5 volts for 30 seconds.
Voltage Reduction Mode
The BCM will enter Voltage Reduction Mode when the
calculated ambient air temperature is above 0°C (32°F).
The calculated battery current is less than 1 ampere and
greater than −7 amperes, and the generator field duty
cycle is less than 99 percent. Its targeted generator
output voltage is 12.9 volts. The BCM will exit this mode
once the criteria are met for Charge Mode.
Instrument Panel Cluster (IPC) Operation
Charge Indicator Operation
The instrument panel cluster (IPC) illuminates the
charge indicator and displays a warning message in the
driver information center (DIC) when the one or more of
the following occurs:
• The engine control module (ECM) detects that the
generator output is less than 11 volts or greater than
16 volts. The IPC receives a GMLAN message from
the ECM requesting illumination.
• The IPC determines that the system voltage is less
than 11 volts or greater than 16 volts for more than 30
seconds. The IPC receives a GMLAN message from
the body control module (BCM) indicating there is a
system voltage range concern.
• The IPC performs the displays test at the start of each
ignition cycle. The indicator illuminates for
approximately 3 seconds.
• The ignition is ON, with the engine OFF.
Battery Voltage
The IPC displays the system voltage as received from
the BCM over the GMLAN serial data circuit. If there is
no communication with the BCM then the display will
read all dashes until communication is restored.
SERVICE BATTERY CHARGING SYSTEM
The BCM and the ECM will send a GMLAN message to
the DIC for the SERVICE BATTERY CHARGING
SYSTEM message to be displayed. It is commanded ON
when a charging system DTC is a current DTC. The
message is turned OFF when the conditions for clearing
the DTC have been met.