Durango 2WD V8-5.7L Hybrid (2009)
Charge Lamp/Indicator: Description and Operation
Charging Indicator - Operation
OPERATION
The charging indicator gives an indication to the vehicle operator when the electrical system voltage is too low or too high. This indicator is controlled
by a transistor on the instrument cluster circuit board based upon cluster programming and electronic messages received by the cluster from the
Powertrain Control Module (PCM) over the Controller Area Network (CAN) data bus.
The charging indicator Light Emitting Diode (LED) is completely controlled by the instrument cluster logic circuit. This logic only allows the indicator
to operate when the instrument cluster receives a battery current input on the fused ignition switch output (run-start) circuit. Therefore, the LED is always
off when the ignition switch is in any position except ON or START. The LED only illuminates when it is provided a path to ground by the instrument
cluster transistor. The instrument cluster turns on the charging indicator for the following reasons:
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Bulb Test - Each time the ignition switch turns to the on position the charging indicator is illuminated by the instrument cluster for about two
seconds as a bulb test.
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Voltage Low Message - Each time the cluster receives an electronic system voltage message from the PCM indicating the voltage is low (less
than about 11.5 volts is a charge fail condition), the charging indicator illuminates. The indicator remains illuminated until the cluster receives a
message from the PCM indicating the voltage is normal (greater than about 12.0 volts, but less than 16.0 volts), or until the ignition switch turns to
the off position, whichever occurs first.
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Voltage High Message - Each time the cluster receives an electronic system voltage message from the PCM indicating the voltage is high (greater
than about 16.0 volts), the charging indicator illuminates. The indicator remains illuminated until the cluster receives a message from the PCM
indicating the voltage is normal (less than about 15.5 volts, but greater than 11.5 volts), or until the ignition switch turns to the off position,
whichever occurs first.
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Self Test - Each time the cluster is put through the self test, the charging indicator turns on, then off again during the bulb check portion of the test
to confirm the functionality of the LED and the cluster control circuitry.
The PCM continually monitors the electrical system voltage to control the generator output. The PCM then sends the proper messages to the instrument
cluster, also known as the Cab Compartment Node (CCN). If the instrument cluster turns on the charging indicator due to a charge fail or voltage high
condition, it may indicate that the charging system requires service. For further diagnosis of the charging indicator or the instrument cluster circuitry that
controls the indicator, See: Instrument Cluster / Carrier/Testing and Inspection.
Use a diagnostic scan tool for proper diagnosis of the charging system, the PCM, the CCN, the CAN data bus or the electronic communication related to
charging indicator operation. Refer to the appropriate diagnostic information.
