C1021moderate severityChassis
Battery Voltage High
on 2012 Jeep Wrangler 3.6L V6 · 4WD
What this code means
The ABS/ESP module detects system voltage above the allowable range. Overvoltage can damage module electronics and disable safety functions.
Symptoms
- ABS and ESP lights on
- Charging system warning
- System functions disabled
Common causes
- Faulty voltage regulator
- Overcharging alternator
- Poor ground connection
- Faulty battery
Diagnostic steps
- Measure charging voltage at battery
- Test alternator regulator
- Check ground circuits
- Verify voltage at module
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Other Chassis codes on this vehicle
C0021
LF Wheel Speed Sensor Range/Performance
C0022
RF Wheel Speed Sensor Range/Performance
C0023
LR Wheel Speed Sensor Range/Performance
C0024
RR Wheel Speed Sensor Range/Performance
C0025
LF Wheel Speed Sensor Circuit Intermittent
C0026
RF Wheel Speed Sensor Circuit Intermittent
C0027
LR Wheel Speed Sensor Circuit Intermittent
C0028
RR Wheel Speed Sensor Circuit Intermittent
C0035
Left Front Wheel Speed Sensor Circuit
C0036
Left Front Wheel Speed Signal Erratic