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P0521

P0521

Diagnosis information - DME (DFI)

Oil pressure sensor implausible


NOTE:
- The engine oil pressure is set by the oil pressure-regulating valve.
- The oil pressure depends on:
- Oil temperature
- Engine speed

- If the oil pressure is outside a defined range, a fault is detected:
- at engine speed less than 1,000 rpm --> required pressure less than 6.2 bar
- at engine speed more than 3,008 rpm --> required pressure more than 1.5 bar
- The measured oil pressure is compared with the ambient pressure in the control unit after-run phase (after ignition off) --> required value less than 0.5 bar difference.

Diagnostic conditions
- Engine idling more than 1 minute, then:
- Engine speed more than 3,010 rpm, then:
- Ignition off and ignition key removed for more than 1 minute

Possible fault causes
- Oil pressure too low
(oil level, oil pump, dirt in oil circuit, oil circuit faulty, etc.)
- Oil pressure sensor faulty (incorrect trimming compared with ambient pressure sensor)