P1594

Tests 1 - 2:

Tests 3 - 6:

Tests 7 - 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
- Target voltage differs from battery voltage
- Intermittent condition
- Ambient/Batt temperature sensor
- Generator field coil short to ground
- Generator field short to ground
- Powertrain control module