# P0521 on the 2021 Chevrolet Trailblazer

The bulletins listed name this code in NHTSA's summary, or are about the same components. A bulletin or a recall listed here may apply to the model year. None of it is a diagnosis.

Nobody has written a description of this code yet.

## Bulletins for this model year that name P0521

- [10251615](https://open.wenmarpro.com/bulletins/10251615), 2024-03-14: Emission Recall. General Motors has decided to conduct a Voluntary Emission Recall involving certain vehicles. The Engine Control Module \(ECM\) may not clear the permanent status of DTC P0521 \(Engine Oil Pressure Sensor Performance\). If the ECM had previously set a DTC P0521 and the permanent status is not properly cleared, the vehicle may not pass certain Emissions Inspection/Maintenance \(I/M\) tests. Dealers are to reprogram the ECM.
- [10227772](https://open.wenmarpro.com/bulletins/10227772), 2022-12-13: Service Update. In certain vehicles, if the Engine Control Module \(ECM\) sets the DTC P0521 \(Engine Oil Pressure Sensor Performance\), the ECM cannot clear the permanent status of this DTC. If the ECM had previously set a DTC P0521 and the permanent status is not properly cleared, the vehicle may not pass certain Emissions Inspection/Maintenance \(I/M\) tests. Dealers are to reprogram the ECM.
- [10206744](https://open.wenmarpro.com/bulletins/10206744), 2022-01-24: This Preliminary information communicates to the dealers information related to isolating a potential engine wiring harness issue causing a MIL on with P0521.
- [10204447](https://open.wenmarpro.com/bulletins/10204447), 2021-12-13: This Preliminary information communicates to the dealers information related to isolating a potential engine wiring harness issue causing a MIL on with P0521.
- [10204444](https://open.wenmarpro.com/bulletins/10204444), 2021-12-13: This Preliminary information communicates to the dealers information related to isolating a potential engine wiring harness issue causing a MIL on with P0521.
- [10177355](https://open.wenmarpro.com/bulletins/10177355), 2020-07-20: Service Update \- On certain vehicles, the engine oil pump may be stuck due to foreign material, and diagnostic trouble codes \(DTC\) P0521, P06DE, P06DD could be set. Dealers are to perform the engine oil pump screening test and if necessary, replace the oil pump.