Diagnostic article Generic OBD-II
P0AF0: Inverter-A circuit high is a cold indication with a startup qualification
Understand the GM P0AF0 temperature-input monitor and the warmup condition applied to a fault present at startup.
Read before applying this article
Documented application
GM 2010 10OBDG10 Hybrid Diagnostics, only the cited controller and monitor. These are historical calibration examples; individual vehicle, engine and hardware applicability is not established.
The code alone does not identify a failed part or establish that a vehicle is safe to drive. Confirm the vehicle, reporting module and applicable service procedure.
P0AF0 is the high-voltage end of inverter A's first temperature-sensor circuit. GM describes PIM Temp 0 below −40°C, corresponding to a signal near 5V. The apparent cold temperature is part of the circuit-fault interpretation, not proof that the inverter is physically that cold.
Startup and warmup affect eligibility
The wakeup signal must be on. If the malfunction exists at the start of the trip, the row adds accumulated inverter warmup time of at least 1.5 minutes above the stated torque threshold. This prevents the startup context from being ignored when interpreting a later recorded failure.
The source lists a 250-of-350 count decision at approximately 10.4ms intervals. The exact row belongs to inverter A's PIM Temp 0 channel and should not be replaced with another sensor's timing.
Keep the channel separate from the average
Record the individual temperature, validity, wakeup state and available warmup history. An inverter average that looks reasonable may still conceal an out-of-range individual input. The companion P0AEE rationality check is a separate diagnostic path.
The table supplies no connector position, resistance curve or proof of a particular open circuit. The applicable inverter service information must determine physical testing and repair. High-voltage access requires a qualified technician following the prescribed isolation and verification process, rather than live probing based on the near-5V description.
Source and applicability
GM 2010 10OBDG10 Hybrid Diagnostics, only the cited controller and monitor. These are historical calibration examples; individual vehicle, engine and hardware applicability is not established. GM PDF, page 289.
Article source documents
Source checks describe how the text was prepared; they do not certify a diagnosis or confirm compatibility with every vehicle using this code.
Original code reference
Dictionary definition
Drive Motor Inverter Temperature Sensor A Circuit High
This definition retains its original catalog scope. The article above is limited to its explicitly documented application.
Reference scope
Generic OBD-II definition.
A manufacturer label does not establish the model, year, engine or module to which a diagnosis applies. Read the safety and diagnostic limits.
Definition source
- DTC Database: pinned community code definitions
Source checked · MIT