Mercedes-Benz W212 DPF differential pressure sensor and fault codes
Where is the W212 DPF differential pressure sensor located?
It depends on the engine. On the OM642 the sensor is in the engine bay on the left of the turbo near the bulkhead, part number A6429050100. On the S212 220 CDI it is behind the air filter housing at the ends of the hoses. The sensor looks like other sensors, so check the part number.
What does a DPF pressure sensor fault code, e.g. P2453, mean?
The code indicates that the sensor voltage is outside the permitted limits. It does not alone prove that the sensor is broken. The cause can also be a hose clogged with soot, a faulty wiring harness or a connector.
What is checked before replacing the sensor and what after replacement?
First check the hoses and wiring harnesses; sooted hoses should be cleaned. If the code returns with a new sensor, the fault is often in the hoses, wiring or a real blockage. After replacement the fault codes are cleared and a basic setting is performed, so let a workshop handle it.