What it means
A general circuit fault on the secondary differential pressure sensor B across the DPF - measures backpressure for the regeneration strategy.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
DPF pressure sensor B measures pressure at its designated points across the particulate filter so the control module can estimate restriction and manage regeneration. P245E indicates a general electrical fault in sensor B's circuit, such as an open, short, poor connection, or failed sensor; it does not by itself establish that the DPF is blocked.
Common causes
Most likely first.
- Open or short in sensor wiring or connector
- Faulty DPF pressure sensor B
- Blocked, cracked, or disconnected pressure-sensor hose
- Poor electrical connection or corrosion
Symptoms
- Check engine light or DPF warning light on
- Power loss / limp mode
- Increased fuel consumption
- Failed forced regeneration attempts
How to diagnose it
- Record freeze-frame data and scan sensor B's signal alongside other DPF pressure readings and related circuit codes.
- Locate pressure sensor B and inspect its connector and wiring for corrosion, loose pins, heat damage, or chafing.
- Check both pressure hoses serving sensor B for disconnection, cracks, blockage, or reversed routing, and verify their routing against vehicle information.
- With the circuit powered as specified, check sensor B's supply, ground, and signal at the connector against the manufacturer's specification.
- If the wiring and hoses are intact, test sensor B and compare its response with the manufacturer's procedure.
Common fixes
- Reconnect or replace a cracked, blocked, or disconnected pressure hose for sensor B.
- Clean and secure corroded or loose sensor B connector terminals.
- Repair an open or shorted section of sensor B wiring.
- Replace DPF pressure sensor B if its circuit checks pass but its output is faulty.
Can I keep driving?
If the vehicle has reduced power or a DPF warning, limit driving and avoid heavy loads until the sensor circuit is repaired. Incorrect pressure data can disrupt regeneration and allow soot loading to increase.
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.