Charge Lamp/Indicator: Description and Operation

CHARGING INDICATOR
Voltage Gauge
A voltage gauge is used only in the high-line instrument clusters. The voltage gauge is located on the left side of the instrument cluster, above the fuel gauge. The voltage gauge consists of a movable gauge needle or pointer controlled by the instrument cluster circuitry and a fixed 90 degree scale on the cluster overlay that reads left-to-right from 9 - 19 volts. An International Control and Display Symbol icon for "Battery Charging Condition" is located on the cluster overlay above the right end of the gauge scale. The gauge needle, gauge scale, and icon are clearly visible on the face of the instrument cluster in daylight, and are illuminated from behind by the panel lamps dimmer controlled cluster illumination lighting when the exterior lamps are turned ON. Cluster illumination is provided by replaceable incandescent bulb and bulb holder units located on the instrument cluster electronic circuit board. The voltage gauge is serviced as a unit with the instrument cluster.

The voltage gauge gives an indication to the vehicle operator of the electrical system voltage. This gauge is controlled by the instrument cluster circuit board based upon the cluster programming and electronic messages received by the cluster from the Powertrain Control Module (PCM) over the Chrysler Collision Detection (CCD) data bus. The voltage gauge is an air core magnetic unit that receives battery current on the instrument cluster electronic circuit board through the fused ignition switch output (START/RUN) circuit whenever the ignition switch is in the ON or START positions. The cluster is programmed to move the gauge needle back to the low end of the scale after the ignition switch is turned to the OFF position. The instrument cluster circuitry controls the gauge needle position and provides the following features:

- Charge Fail Message - Each time the cluster receives a message from the PCM indicating a charge fail condition (system voltage is 9 volts or lower), the gauge needle is moved to the 9-volt graduation on the gauge scale and the check gauges indicator is illuminated. The gauge needle remains ON the 9-volt graduation and the check gauges indicator remains illuminated until the cluster receives a message from the PCM indicating there is no charge fail condition (system voltage is 12 volts or higher, but lower than 19 volts), or until the ignition switch is turned to the OFF position, whichever occurs first.

- Voltage High Message - Each time the cluster receives a message from the PCM indicating a voltage high condition (system voltage is 19 volts or higher), the gauge needle is moved to the 19-volt graduation on the gauge scale and the check gauges indicator is illuminated. The gauge needle remains ON the 19-volt graduation and the check gauges indicator remains illuminated until the cluster receives a message from the PCM indicating there is no voltage high condition (system voltage is 16 volts or lower, but higher than 9 volts), or until the ignition switch is turned to the OFF position, whichever occurs first.

- Message Failure - If the cluster fails to receive a system voltage message, it will hold the gauge needle at the last indication until a new message is received, or until the ignition switch is turned to the OFF position, whichever occurs first.

- Actuator Test - Each time the cluster is put through the actuator test, the gauge needle will be swept to several calibration points on the gauge scale in a prescribed sequence to confirm the functionality of the gauge and the cluster circuitry.

The PCM continually monitors the system voltage to control the generator output. The PCM then sends the proper system voltage messages to the instrument cluster. For further diagnosis of the voltage gauge or the instrument cluster circuitry that controls the gauge, (Refer to INSTRUMENT CLUSTER - DIAGNOSIS AND TESTING). If the instrument cluster turns ON the check gauges indicator due to a charge fail or voltage high condition, it may indicate that the charging system requires service. For proper diagnosis of the charging system, the CCD data bus, or the message inputs to the instrument cluster that control the voltage gauge, a DRB III scan tool and the appropriate diagnostic information are required.

Voltage Warning Lamp
A voltage warning lamp is used only in the low-line instrument clusters. The voltage warning lamp is located on the left side of the instrument cluster overlay, above the fuel door location indicator. The voltage warning lamp consists of a red lens behind a round cutout in the instrument cluster overlay. An International Control and Display Symbol icon for "Battery Charging Condition" is imprinted in black near the center of the red lens. The icon is clearly visible on the face of the instrument cluster when the lamp is not illuminated, and is silhouetted in a bright red glow when the voltage lamp is illuminated from behind by a replaceable incandescent bulb and bulb holder unit located on the instrument cluster electronic circuit board. The voltage warning lamp is serviced as a unit with the instrument cluster.

The voltage warning lamp gives an indication to the vehicle operator when the electrical system voltage is too low or too high. This lamp is controlled by the instrument cluster circuit board based upon the cluster programming and electronic messages received by the cluster from the Powertrain Control Module (PCM) over the Chrysler Collision Detection (CCD) data bus. The voltage warning lamp bulb receives battery current on the instrument cluster electronic circuit board through the fused ignition switch output (START/RUN) circuit whenever the ignition switch is in the ON or Start positions; therefore, the lamp will always be OFF when the ignition switch is in any position except ON or START. The lamp bulb only illuminates when it is switched to ground by the instrument cluster circuitry. The instrument cluster will turn ON the voltage warning lamp for the following reasons:

- Bulb Test - Each time the ignition switch is turned to the ON position the lamp is illuminated for about three seconds.

- Charge Fail Message - Each time the cluster receives a message from the PCM indicating a charge fail condition (system voltage is nine volts or lower), the lamp will be illuminated. The lamp remains illuminated until the cluster receives a message from the PCM indicating there is no charge fail condition (system voltage is 12 volts or higher, but lower than 19 volts), or until the ignition switch is turned to the OFF position, whichever occurs first.

- Voltage High Message - Each time the cluster receives a message from the PCM indicating a voltage high condition (system voltage is 19 volts or higher), the lamp will be illuminated. The lamp remains illuminated until the cluster receives a message from the PCM indicating there is no voltage high condition (system voltage is 16 volts or lower, but higher than 9 volts), or until the ignition switch is turned to the OFF position, whichever occurs first.

- Actuator Test - Each time the cluster is put through the actuator test, the lamp will be turned ON and OFF in a prescribed sequence to confirm the functionality of the lamp and the cluster circuitry.

The PCM continually monitors the system voltage to control the generator output. The PCM then sends the proper system voltage messages to the instrument cluster. If the voltage warning lamp fails to light during the bulb test, replace the bulb with a known good unit. For further diagnosis of the voltage warning lamp or the instrument cluster circuitry that controls the lamp, (Refer to INSTRUMENT CLUSTER - DIAGNOSIS AND TESTING). If the instrument cluster turns ON the lamp after the bulb test, it may indicate that the charging system requires service. For proper diagnosis of the charging system, the CCD data bus, or the message inputs to the instrument cluster that control the voltage warning lamp, a DRB III scan tool and the appropriate diagnostic information are required.