What it means
The particulate matter sensor heater control circuit is reading above its expected range.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The PM sensor heater control circuit operates the heater that brings the exhaust sensor to working temperature. This code sets when the module sees a circuit reading above its expected range, which may indicate a control wire shorted to supply or an abnormal connection.
Common causes
Most likely first.
- Control line shorted to supply
- Connector pins corroded - high contact resistance
- Supply wire pinched against B+ source
Symptoms
- Check-engine light on
- Particulate matter sensor or aftertreatment warning
- Emissions inspection failure
How to diagnose it
- Record freeze-frame data and check for related PM sensor heater codes before clearing anything.
- Inspect the heater connector and exhaust harness for corrosion, pin damage, melted insulation, or contact with a power wire.
- Compare the commanded heater state with live circuit data to confirm whether the high reading is present now.
- Test the heater control wire for an unintended short to supply and inspect connector contact resistance using the manufacturer's wiring information.
- If the external circuit is sound, test the heater and its control circuit following the manufacturer's diagnostic procedure.
Common fixes
- Repair a control wire shorted to a supply wire.
- Replace heat-damaged or pinched heater wiring.
- Clean or repair corroded connector terminals.
- Replace the PM sensor if testing confirms an internal heater circuit fault.
Can I keep driving?
Cautious driving is generally possible if there is no loss of power, but have the fault repaired soon. The heater may not operate correctly, leaving particulate monitoring unreliable and potentially causing an emissions warning.
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.