P0521 2011 Chevy

ChevyDude

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Make
Chevrolet
Model
Silverado
Year
2011
Miles
30k miles
Engine
5.3
Got my dad's truck, 2011 Silverado Flexfuel 5.3L 30k miles threw a code P0521.

Any ideas are appreciated.

Thanks,

cd
 

billr

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Any time engine oil pressure is in question, my first impulse is to connect a mechanical gauge and check pressure. Once you know there is sufficient pressure we can start looking into why the sensor circuit is setting that code.
 

ChevyDude

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Any time engine oil pressure is in question, my first impulse is to connect a mechanical gauge and check pressure. Once you know there is sufficient pressure we can start looking into why the sensor circuit is setting that code.
Thanks! What should the proper psi be? Is the sensor a common problem?
 

billr

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When you first start it cold it will be on a "fast idle". I would expect 20 psig minimum. I will look later for info on the sensor/circuit. Will be looking on <charm.li> You may want to start looking there, too.
 

billr

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OP, are you still with me? I finally peeked at info on that EOP sensor.

Oops, I wrote this earlier, but didn't post it!
 

grcauto

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Operation CHARM: Car repair manuals for everyone.
Home >> Chevy Truck >> 2011 >> Silverado 1500 2WD V8-5.3L >> Repair and Diagnosis >> A L L Diagnostic Trouble Codes ( DTC ) >> Testing and Inspection >> P Code Charts >> P0521

P0521​



DTC P0521, P0522, or P0523

Diagnostic Instructions


* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions)provides an overview of each diagnostic category.

DTC Descriptors
DTC P0521
- Engine Oil Pressure (EOP) Sensor Performance

DTC P0522
- Engine Oil Pressure (EOP) Sensor Circuit Low Voltage.

DTC P0523
- Engine Oil Pressure (EOP) Sensor Circuit High Voltage

Diagnostic Fault Information

140871825




Circuit/System Description

The engine oil pressure (EOP) sensor changes voltage based on the engine oil pressure. The EOP sensor is a 3-wire sensor comprising of the signal circuit, the low reference circuit and the 5 V reference circuit. The engine control module (ECM) supplies 5 V to the EOP sensor via the 5 V reference circuit and provides ground via the EOP low reference circuit. The ECM monitors the signal circuit of the EOP sensor to determine the EOP sensor voltage is within the normal operating range of approximately 1-4 V. When the engine oil pressure is high, the EOP sensor voltage is high and the ECM senses a high signal voltage. When the engine oil pressure is low, the EOP sensor voltage is low and the ECM senses a low signal voltage. The ECM sends the EOP information via the serial data circuit to the body control module (BCM). The BCM then sends the EOP information to the instrument panel cluster (IPC) via the serial data circuit.

Conditions for Running the DTC

The engine is running.

Conditions for Setting the DTC

P0521


The ECM detects that the difference between the predicted oil pressure and the actual oil pressure is either less than 47 kPa (6.8 psi) or greater than 50 kPa (7.3 psi).

P0522
* The ECM detects that the EOP sensor signal circuit is less than 0.1 V.
* The above condition is present for greater than 10 seconds.

P0523
* The ECM detects that the EOP sensor signal circuit is greater than 4.4 V.
* The above condition is present for greater than 10 seconds.

Action Taken When the DTC Sets

* The ECM records the operating conditions at the time the diagnostics test fails. The ECM displays this information in the Failure Records on the scan tool.
* The IPC illuminates the EOP indicator.

Conditions for Clearing the DTC

* The DTC becomes history when the conditions for setting the DTC are no longer present.
* The history DTC clears after 40 malfunction-free warm-up cycles.

Reference Information
Schematic Reference


Instrument Cluster Schematics (Instrument Cluster Schematics)
Connector End View Reference

Component Connector End Views (Connector End Views By Name)
Description and Operation

Instrument Cluster Description and Operation (Instrument Cluster)
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

Scan Tool Reference

Control Module References (Control Module References)for scan tool information

Circuit/System Verification

1. Engine running, observe the scan tool Engine Oil Pressure Sensor parameter. The reading should be between 41-448 kPa (6-65 psi).
2. Verify the engine oil pressure, refer to the following listed below:

* Oil Pressure Diagnosis and Testing (Oil Pressure Diagnosis and Testing)for the 4.8L, 5.3L, 6.0L, 6.2L and 7.0L engine.
* Oil Pressure Diagnosis and Testing (Oil Pressure Diagnosis and Testing)for the 4.3L engine.
* Oil Pressure Diagnosis and Testing (Oil Pressure Diagnosis and Testing)for the 6.6L engine

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the engine oil pressure (EOP) sensor.
2. Ignition OFF, test for less than 1.0 ohm between the low reference circuit terminal listed below and ground:

* Low Reference Terminal 3 (Gas)
* Low Reference Terminal 1 (Diesel)

• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.

3. Ignition ON, test for 4.8-5.2 V between the 5- V reference circuit terminal listed below and ground:

* 5 V Reference Terminal 2 (Gas)
* 5 V Reference Terminal 3 (Diesel)

• If less than the specified range, test the 5 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.

• If greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.

4. Verify the scan tool Engine Oil Pressure Sensor parameter is less than 8 kPa (1.2 psi).

• If greater than the specified range, test the signal circuit terminal listed below for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.

* Signal Terminal 1 (4.8L, 5.3L or 6.0L Gas)
* Signal Terminal 2 (6.6L Diesel)
* Signal Terminal 3 (4.3L Gas)

5. Install a 3 A fused jumper wire between the signal circuit terminal and the 5 V reference circuit terminal listed below. Verify the scan tool Engine Oil Pressure Sensor parameter is greater than 550 kPa (80 psi).

* Signal Terminal 1 (4.8L, 5.3L or 6.0L Gas)
* Signal Terminal 2 (6.6L Diesel)
* Signal Terminal 3 (4.3L Gas)
* 5 V Reference Terminal 2 (Gas)
* 5 V Reference Terminal 3 (Diesel)

• If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.

6. If all circuits test normal, test or replace the EOP sensor.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Engine Oil Pressure Sensor and/or Switch Replacement (Service and Repair)for the 4.3L engine
* Engine Oil Pressure Sensor and/or Switch Replacement (Service and Repair)for the 4.8L, 5.3L, 6.0L, and 6.2L engines
* Engine Oil Pressure Sensor and/or Switch Replacement (Service and Repair)for the 6.6L engine
* Control Module References (Control Module References)for ECM replacement, setup, and programming

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billr

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Do you have reasonable access to that EOP sensor? Are you able to get a gauge/hose in there to check pressure when the engine is running?
 

ChevyDude

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Do you have reasonable access to that EOP sensor? Are you able to get a gauge/hose in there to check pressure when the engine is running?

Thanks for the info. I am trying to find the time to troubleshoot and it's not working out. If not by this weekend, to the shop it goes.
 
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