Powertrain, generic · Hybrid propulsion

P0AB0 Hybrid/EV Battery Pack Air Temperature Sensor A Circuit Intermittent/Erratic

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

P0AB0 flags a battery air temperature sensor A signal that jumps faster than real air temperature can change, usually a sign of a loose contact rather than a dead sensor. No manufacturer documents this exact code publicly; GM's two-mode and 2013 tables for sensor A only list the low, high and plausibility codes. GM does describe the method for the analogous cell sensor code P0A9F: the controller adds up the absolute signal changes over a 10-sample window and fails it when the sum exceeds a limit, 4 of 5 windows, Type B. CARB requires hybrid temperature inputs to be checked for such faults. Wiggle-test harness and connector at the inlet duct while watching live data before replacing the sensor.

Likely causes

Loose or corroded contact at the inlet air sensor connector
Wire chafed through at the duct, intermittently touching ground
Electrical interference on the sensor line

Symptoms

  • Hybrid warning light that comes and goes
  • Inlet air reading jumps in live data
  • Battery fan speed changes without obvious reason

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€80–500
Time0.5–3 h

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

Parts involved

hv battery pack air temp sensor awiring harnessbms

Related codes

P0AACP0AADP0AAEP0AAFP0AB5

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