OBD-II code · Powertrain (generic, extended)
P2037 Reductant Injection Air Pressure Sensor A Circuit
A general electrical fault is reported on reductant injection air-pressure sensor A — used on air-assisted DEF dosing systems to monitor the atomisation air pressure delivered to the injector.
Is it safe to drive with P2037?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyAir pressure sensor failed
- PossibleHarness fault between sensor and PCM
Symptoms
- Check engine light or NOx warning on
- AdBlue/DEF level or quality warning
- Possible no-start countdown after ignore period
- Failed emissions inspection (NOx)
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 0.7–2 h
- Emissions test
- Likely to fail
- Parts involved
- Reductant Air Pressure Sensor, Reductant Air Pump
Related codes
- P209AReductant Injection Air Pressure Sensor B Circuit
- P2034Exhaust Gas Temperature Sensor Circuit (Bank 2 Sensor 2)
- P2035Exhaust Gas Temperature Sensor Circuit Low (Bank 2 Sensor 2)
- P2036Exhaust Gas Temperature Sensor Circuit High (Bank 2 Sensor 2)
- P2038Reductant Injection Air Pressure Sensor A Circuit Range/Performance
- P2039Reductant Injection Air Pressure Sensor A Circuit Low
- P203AReductant Level Sensor A Circuit
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.