P0E94

Code

Generic P — Powertrain

Drive Motor B Inverter Voltage Sensor B” Circuit High

Brand: Generic

Type: P — Powertrain

Views: UK: 23 EN: 31 RU: 25

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Faulty inverter voltage sensor (sensor B)
Open or shorted wiring between inverter and controller (short to battery positive or other high-voltage source)
Poor or corroded connector/terminal at sensor or controller
Faulty inverter control module or internal sensor circuitry
High-voltage supply anomaly (unexpectedly high DC bus voltage or surge)
Fault in controller’s reference/ground or ADC input

Read freeze frame and diagnostic data: capture live sensor voltage and related HV bus voltage
Check for additional DTCs that may indicate HV supply or ground issues
Visually inspect inverter, harness, and connectors for damage, heat discoloration, or corrosion
Verify connectors are fully seated and locking tabs intact
Measure sensor signal voltage at the sensor connector and at the controller/inverter harness (compare both ends)
Measure continuity/resistance of wiring between sensor and controller/inverter with power off and HV system disabled

Sensor output is a scaled representation of the HV DC bus; control modules typically expect a low-voltage signal proportional to HV bus
Expected signal typically in low-voltage range (e.g., 0–5 V) depending on vehicle — verify vehicle-specific nominal and threshold values
Fault is logged when the sensor signal exceeds the controller's upper threshold (signal-high condition)
HV bus actual voltage (pack voltage) should be checked simultaneously — abnormalities in HV bus may correlate with high sensor reading

Record codes, freeze frame, and live data. Note sensor B voltage, HV bus voltage, and related parameters.
Attempt a key cycle and clear the code. See if the code returns and under what conditions it sets.
Perform a visual inspection of inverter B, harnesses, and connectors for damage, melting, or contaminants.
Verify safety: disable high-voltage system and follow the manufacturer’s HV safety procedure before touching harnesses or connectors.
With HV disabled, disconnect the sensor/inverter connector and inspect pins for corrosion, bent pins, or contamination.
With appropriate PPE and tools, measure the sensor output voltage at the connector with the system in the commanded state per service manual. Compare to vehicle-specific expected values.
Check continuity and insulation: measure resistance between the sensor signal wire and vehicle positive HV bus and ground to detect shorts.
Verify the controller/inverter reference ground and supply voltages to the sensing circuit.
If wiring and connectors are good, test or replace the inverter voltage sensor or inverter assembly per service procedures. If available, swap with a known-good unit or harness to isolate the fault.
After repairs, clear codes and perform a road/functional test to confirm the fault does not recur. Re-scan for related DTCs and recheck live data.