Powertrain, generic (extended)

P2CC2 Generator Voltage Sense Circuit B Range/Performance

Check engine lightUsually off
EmissionsNot relevant
Drive cycleRequired
Limp modeNo

P2CC2 means the voltage arriving on generator sense circuit B is within electrical limits but does not agree with what the controller expects, such as the battery voltage measured elsewhere, the commanded set point or the reading of sense circuit A. The usual cause is a voltage drop: corroded ring terminals, a loose ground strap or a damaged fusible link make the sensed value lag behind reality. Because the sense lead itself carries no current, any noticeable difference between it and the output terminal points to resistance in one of the paths. No manufacturer documents P2CC2 publicly. CARB only requires charging-system inputs to be monitored when they influence emissions or feed other diagnostics, so the code often stays without MIL. Circuit A's equivalent is P063B.

Likely causes

Voltage drop from corroded terminals, loose ground strap or damaged fusible link
Alternator B delivering too little or unstable output
Battery with high internal resistance distorting the comparison

Symptoms

  • Charging warning lamp on or flickering
  • Battery not fully charged or charging voltage fluctuating

Repair estimate

DifficultyMediumDIY possible
Parts and labour€20–700
Time0.5–2.5 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

generator voltage sense circuitalternatorwiring harness

Related codes

P2CC1P2CC3P2CC4P063BP0562P0563

References: autoprollc.com, law.cornell.edu, serdia.deutz.com.