Powertrain, generic (extended)

P2DC3 Starter/Generator Phase Y Current Sensor Circuit

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P2DC3 flags an electrical fault in the circuit of the phase Y current sensor of the starter/generator. Such a sensor needs a supply, a ground and a signal line, and a break or short in any of the three can end up here when the controller cannot or does not tell high from low. Under CARB's rule the hybrid parts a manufacturer chooses to monitor are checked like any other input component, and the manufacturer has to get its hybrid monitoring plan approved. Not every machine has a Y sensor: GM's eAssist table covers only phases U and W, so a vehicle storing P2DC3 uses a different layout. No manufacturer documents P2DC3 publicly. Measure supply and ground at the sensor plug before condemning the machine. Range check: P2DC4; high and low: P2D93, P2D96.

Likely causes

Missing supply or ground at the phase Y sensor
Open phase Y signal line between sensor and controller
Phase Y current sensor without output

Symptoms

  • MIL or hybrid warning
  • Automatic stop-start disabled
  • Battery charged less by the starter/generator

Repair estimate

DifficultyHardWorkshop job
Parts and labour€150–2,000
Time0.5–4 h

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

Parts involved

starter generator phase y current sensorwiring harnessstarter generator control module

Related codes

P2DC4P2D93P2D96P2D99P2DC1P2DC5

References: law.cornell.edu, gsi.ext.gm.com.