U05A4
Particulate Matter Sensor Received Invalid Data From ECM/PCM
The particulate matter (PM) sensor (smart sensor with own ECU) received implausible data from the ECM/PCM. Engine load, exhaust temperature or DPF state data needed for compensation fails plausibility checks; PM readings are degraded.
The particulate matter (PM) sensor (smart sensor with own ECU) received implausible data from the ECM/PCM. Engine load, exhaust temperature or DPF state data needed for compensation fails plausibility checks; PM readings are degraded.
Common causes
- high
ECM/PCM internal fault or sensor input drift
One of the most commonly reported causes for this code — check this first.
Typical part cost: $330-2750
- medium
Software version mismatch after replacement
A plausible cause — test and verify before replacing parts.
Typical part cost: $330-2750
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
See related trouble codes
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Frequently asked questions
What does U05A4 mean?
U05A4 means "Particulate Matter Sensor Received Invalid Data From ECM/PCM". It is a generic OBD-II code that points to a fault in the network / communication.
What are the most common causes of U05A4?
ecm/pcm internal fault or sensor input drift; software version mismatch after replacement; gateway module routing can messages incorrectly — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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