P1594

Tests 1 - 3:

Tests 4 - 8:

SYMPTOM
P1594-CHARGING SYSTEM VOLTAGE TOO HIGH

WHEN MONITORED
With the ignition key ON and the engine speed greater than 0 RPM.

SET CONDITION
When the PCM regulates the generator field and there are no detected field problems, but the voltage output does not decrease.

POSSIBLE CAUSES
- Ambient/Batt temperature sensor
- Generator field driver circuit shorted to ground
- Generator field shorted to ground
- Ambient/Batt temperature sensor
- Powertrain control module (battery voltage)
- Powertrain control module (generator resistance)