What it means
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.
At a glance
- Usually lights the warning light of the system that lost communication
- Affects emissions; the car can fail an emissions test
How it works
The particulate matter sensor has its own control unit and reports soot-related readings used to assess exhaust and DPF operation. It also needs compensation data from the ECM/PCM, such as engine load, exhaust temperature, and DPF state; this code sets when that data is judged implausible and the sensor's readings are treated as degraded.
Common causes
Most likely first.
- ECM/PCM internal fault or sensor input drift
- Software version mismatch after replacement
- Gateway module routing CAN messages incorrectly
Symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
How to diagnose it
- Save freeze-frame data and scan all modules for communication and related engine or DPF codes to see when the PM sensor data became invalid.
- Compare live engine load, exhaust temperature, and DPF state values with other scan data and check whether any are implausible or missing.
- Inspect the PM sensor and ECM/PCM connectors and the related wiring and CAN connections for damage, corrosion, loose pins, or poor grounds.
- Check for other ECM/PCM input faults that could make its load, temperature, or DPF messages implausible.
- Verify that the ECM/PCM, PM sensor, and gateway software and configuration are compatible, especially after a module or sensor replacement.
- If the inputs, wiring, and configuration check out, use manufacturer-approved network tests to isolate a gateway routing fault or ECM/PCM or PM sensor control-unit fault.
Common fixes
- Repair loose, corroded, or damaged connectors and wiring in the PM sensor or CAN circuit.
- Correct any engine, exhaust-temperature, or DPF input fault that is making the ECM/PCM data implausible.
- Update or configure the ECM/PCM, PM sensor, or gateway to compatible software after replacement.
- Replace a confirmed faulty gateway, ECM/PCM, or PM sensor control unit.
Can I keep driving?
If the vehicle runs normally and has no other warnings, limit driving and arrange diagnosis soon because unreliable PM data can impair DPF monitoring and emissions control. Stop if it loses power, enters limp mode, or develops signs of overheating or an exhaust fault.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.