Powertrain, generic · Hybrid propulsion

P0AF5 Drive Motor Inverter Temperature Sensor B Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

P0AF5 means inverter temperature sensor B delivers a voltage above its valid range. For GM's NTC sensor that equals an implausibly cold inverter, so an open circuit, a lost ground or a cracked thermistor is likely. In GM's 2016 to 2019 tables the code sets below -50 °C for 2.6 of 3.65 s, but only once the inverter has run at least 90 s at 20 Nm or more, which rules out a genuinely cold start; Type B, two trips. The 2011 Volt uses below -58 °C with Type A, one trip; the 2011 and 2013 two-mode trucks use below -40 °C, Type B. Until the value is valid, the controller protects inverter B with substitute values and may reduce motor B power. Check connectors at the inverter before condemning the unit.

Likely causes

Open sensor or circuit inside the power inverter module
Loose, corroded or unplugged connector at the inverter
Lost sensor ground

Symptoms

  • Malfunction indicator lamp after two trips
  • Reduced motor B power
  • Implausibly cold inverter temperature in live data

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€100–5,000
Time0.5–6 h

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

Parts involved

drive motor inverter temp sensor bhybrid control modulewiring harness

Related codes

P0AF4P0AF2P0AF3P0AF6P0AF0

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