P2453 (DPF Pressure Sensor Circuit) on VAG TDI
On VAG diesels, P2453 is commonly caused by sensor drift, blocked hoses, or wiring issues. Treat it as a measurement fault first—bad readings can create false DPF ‘blocked’ behaviour.
What it usually means on VAG
The ECU is not happy with the differential pressure sensor signal (plausibility, range, or electrical integrity). When the sensor reads wrong, the ECU can overestimate soot load and trigger regen/limp strategies.
Quick checks that catch most cases
- Inspect both pressure hoses from DPF to sensor for splits, kinks, melted sections, or blockage.
- Check the sensor connector for corrosion/loose pins and the loom for chafing.
- Compare sensor reading at key-on engine-off (should be near zero) and at idle.
- If possible, back-to-back compare with a known-good sensor or validate with a manometer.
How it links to other codes
- P2002 / P2463 can be secondary if soot load is being calculated from bad pressure data
- Underboost codes can appear when the ECU limits torque during ‘DPF protection’
When NOT to panic
- If it appeared after a deep puddle / water exposure (connectors dry out and recover)
- If the car drives normally and the code is stored only
Common misdiagnoses
- Replacing the DPF because the car ‘thinks’ it’s blocked
- Ignoring hoses and fitting sensors repeatedly