Powertrain, generic (extended)

P2D95 Starter/Generator Phase X Current Sensor Circuit Low

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P2D95 means the phase X current sensor of the starter/generator delivers a signal below the lowest value the controller accepts. The machine works as motor and as generator, so its phase currents change direction and the sensor reports signed values; GM's eAssist table, for example, uses limits of minus and plus 440 A. Low therefore does not mean little current, but an implausibly large reading in the negative direction or an output that has collapsed. Likely reasons are a signal wire shorted to ground, a lost sensor supply or a broken sensor. No manufacturer documents P2D95 publicly; in the GM analogue the U-phase low code sets below -440 A as a two-trip Type B fault. P2D92 is the high side, P2DC1 the general phase X circuit fault and P2DC2 its range check.

Likely causes

Phase X sensor signal wire shorted to ground or housing
Sensor supply voltage missing because of an open wire or terminal
Current sensor output failed at the lower end of its range

Symptoms

  • Warning lamp after repeated detection
  • Starter/generator runs in a restricted mode with less torque
  • Stop-start unavailable

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 x current sensorwiring harnessstarter generator control module

Related codes

P2D92P2D96P2D97P2DC1P2DC2P2D98

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