P2CC4 code meaning
Generator Voltage Sense Circuit B High
What P2CC4 means
P2CC4 indicates that generator sense circuit B reads above its upper limit. Either the line is shorted to a higher voltage, or the voltage at the measuring point really is excessive, for example because the regulator keeps the field fully energised; Remy warns that a full-field alternator can quickly push the system above 16 V. A meter separates the two cases: with the engine running, compare the sense voltage with the voltage directly at the battery posts. No manufacturer documents P2CC4 publicly. CARB does not require a MIL for charging inputs unless emissions or other monitors are affected, so the battery warning light is the more likely signal. Sustained overvoltage can damage lamps and electronics. Low signal: P2CC3; circuit A high: P063D.
P2CC4 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor0.5 to 2.5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P2CC4
- Charging warning lamp on
- Very high system voltage, bulbs failing early
- Battery gassing or smelling
Common causes of P2CC4
- PossibleRegulator of alternator B stuck in full field, real overvoltage
- PossibleSense wire B shorted to a higher-voltage line
- Less likelySense input of the engine control module faulty
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Generator voltage sense circuitAlternatorWiring harness
What each part of P2CC4 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| C | Area: hybrid propulsion. |
| C4 | The exact fault in that area. |
What to do next
- Note P2CC4 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P2CC4
What does P2CC4 mean?
P2CC4 means "Generator Voltage Sense Circuit B High". P2CC4 indicates that generator sense circuit B reads above its upper limit. It is a generic code, so it means the same on every make.
Is it safe to drive with P2CC4?
P2CC4 does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will P2CC4 fail an emissions test?
P2CC4 is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is P2CC4 to fix?
Difficulty: medium. A typical repair takes 0.5 to 2.5 hours of work. This is a job for a workshop.
Will P2CC4 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.