Powertrain, generic · Hybrid propulsion

P0A88 14 Volt Power Module Current Sensor A Circuit Low

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

P0A88 reports that the current sensor of the 14 V power module (DC/DC converter feeding the 12 V system) reads too low while the converter should be delivering power. GM documents it for the Accessory Power Module: in the 2013 eAssist tables the input current must stay below 0.5 A for 1.5 s within a 2 s window while calculated output power is 0.25 to 1.5 kW; the 2016 tables use 0.50 A or less in 640 of 800 samples, enabled only when the APM is on, the hood is closed and the 12 V target is reached. Both rate it Type B, two trips to MIL. A short to ground, an open signal line or a dead sensor are typical; P0A89 is the opposite high fault, P0A87 the plausibility check.

Likely causes

Sensor signal shorted to ground or open
Current sensor in the power module failed
Corroded or loose module connector

Symptoms

  • MIL and hybrid/charging warning
  • 12 V battery not charged properly
  • Start/stop function may be disabled

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€100–1,800
Time1–4 h

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

Parts involved

pm14v current sensor awiring harnessdcdc converter

Related codes

P0A86P0A87P0A89P0A8AP0C9E

References: gsi.ext.gm.com, gsi.ext.gm.com.