Symptom:
P-1682 CHARGING SYSTEM VOLTAGE TOO LOW
When Monitored and Set Condition:
P-1682 CHARGING SYSTEM VOLTAGE TOO LOW
When Monitored: With no other charging system codes set. With the ignition on and the
engine running above 1500 RPM.
Set Condition: The battery sensed voltage is 1 volt below the charging system goal for 25
seconds. The PCM senses the battery voltage, turns off the field driver and senses the
battery voltage again. If the voltages are the same, the code is set.
POSSIBLE CAUSES
ASD RELAY OUTPUT CIRCUIT OPEN
GENERATOR FIELD DRIVER CIRCUIT OPEN
GENERATOR DEFECTIVE
GENERATOR DEFECTIVE (B)
PCM DEFECTIVE
TEST ACTION APPLICABILITY
1 Start engine, and allow it to idle.
Note: Battery must be fully charged.
Note: Generator Belt tension and condition must be checked before con-
tinuing.
With the DRB, read the Target Charging voltage.
Is the Target Charging voltage above 15.1 volts?All
Ye s®Go To 2
No®Go To 6
2 Ignition On, Engine Not Running
Using DRB Temperature Probe, measure the under hood temperature near PCM.
With the DRB, read the Ambient/BAT Temp.
Is the battery temperature within þ12 degrees C (10 degrees) of the under hood
temperature?All
Ye s®Go To 3
No®Replace the PCM.
Perform Powertrain Verification Test VER-3A.
21
CHARGING
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