What it means
Same as P24AE with the signal voltage below the plausible range. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The particulate matter sensor measures soot downstream of the diesel particulate filter to help the control module assess filter performance and regeneration. P24B0 sets when the sensor signal falls below the module's plausible range, often because the signal wire is shorted to ground or its connector has a poor connection. The module may then lose a reliable soot measurement.
Common causes
Most likely first.
- Signal shorted to ground
- Connector pins corroded - high contact resistance
- Harness chafing through insulation
Symptoms
- Check-engine light on
- Possible emissions warning
- Possible reduced engine power
How to diagnose it
- Record freeze-frame data and check whether the PM sensor signal stays low or changes when the fault occurs.
- Inspect the downstream sensor connector for water, corrosion, and pushed-back pins, then check the harness for chafing or insulation rubbed through to ground.
- With the sensor circuit active, perform a careful harness wiggle test while watching the signal to help locate an intermittent short.
- Using the manufacturer's procedure, test the signal wire for a short to ground and verify sensor power and ground.
- If the wiring and feeds are sound, test the PM sensor for an internal low-output fault.
Common fixes
- Dry and clean the sensor connector and secure its terminals.
- Repair chafed signal-wire insulation where it contacts ground.
- Replace a pushed-back or corroded connector terminal.
- Repair a sensor power or ground fault identified by testing.
- Replace the PM sensor if it continues to produce a low signal with a sound circuit.
Can I keep driving?
A short, gentle trip is generally reasonable if the engine runs normally, but avoid leaving the fault unresolved because the control module may lose DPF soot monitoring and reduced power or emissions problems can follow. Arrange diagnosis promptly if the warning is accompanied by reduced power.
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.