Diagnostic article Generic OBD-II
P0AF5: Inverter-B sensor high is a cold-limit test with warmup context
Read the GM P0AF5 temperature-input criterion and distinguish it from a real low-temperature operating condition.
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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.
P0AF5 evaluates the high-voltage end of inverter B's first temperature-sensor input. In this GM table, PIM Temp 0 falls below −40°C while the associated signal is near 5V. The code is an electrical range diagnosis, not a direct statement about ambient weather or actual inverter temperature.
A fault present at startup has another prerequisite
Wakeup must be on. When the malfunction exists at trip start, the table also requires at least 1.5 minutes of cumulative inverter warmup above its stated torque threshold. The row's sample decision uses 250 failing counts within 350 at approximately 10.4ms intervals.
Those details make the event sequence relevant. A cold initial value and a later failure report need to be interpreted with the warmup context rather than assumed to be simultaneous.
Keep inverter identity attached to the data
Record inverter B's PIM Temp 0, validity and available warmup information. Do not substitute a value from inverter A or assume the generic sensor-B label names a second sensor within the same inverter. The source explicitly uses inverter B sensor one here.
The table provides no proof of an open connector or a failed sensor, and no safe test-point instructions. Physical diagnosis requires the correct inverter service information and a trained high-voltage technician following the prescribed isolation and verification procedure before access.
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 301.
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 B 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