DTC P0069
Diagnostic Instructions
DTC Descriptor
DTC P0069 5A: Manifold Absolute Pressure (MAP) - Barometric Pressure (BARO) Not Plausible
Circuit/System Description
The turbocharger pressure sensor responds to pressure changes in the inlet manifold. The pressure changes occur based on the engine load, and turbocharger boost. The engine control module (ECM) supplies 5-volt to the turbocharger pressure sensor on the 5-volt reference circuit. The ECM provides an ground on the low reference circuit. The turbocharger pressure sensor provides a signal to the ECM on the sensor signal circuit which is relative to the pressure changes in the manifold. The ECM detects a low signal voltage at a low MAP, such as during deceleration. The ECM detects a high signal voltage at a high MAP, such as the ignition is ON, with the engine OFF, or at idle. The barometric pressure (BARO) sensor is internal to the ECM. This location allows for constant monitoring of the barometric pressure. The ECM compares the turbocharger pressure sensor signal to the internal BARO sensor signal when the ignition switch is turned ON, with the engine OFF.
Conditions for Running the DTC
• | DTCs P0105, P0107, or P0108 are not set. |
• | The DTC runs continuously when the above conditions are met. |
Conditions for Setting the DTC
The ECM detects that the difference between the MAP signal and the BARO signal is greater than 20 kPa (2.9 PSI) for 1 s.
Action Taken When the DTC Sets
DTC P0069 is a Type B DTC.
Conditions for Clearing the DTC
DTC P0069 is a Type B DTC.
Diagnostic Aids
• | If a shared 5-volt reference circuit is shorted to ground or shorted to a voltage, other 5-volt reference circuits may be affected. |
• | The scan tool 5-volt reference parameters should display OK. |
Reference Information
Schematic Reference
Engine Controls Schematics : LLW
Connector End View Reference
Component Connector End Views
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Special Tools
EN 23738-A Mityvac
For equivalent regional tools, refer to Special Tools .
Circuit/System Verification
- Ignition ON, observe the DTC information with a scan tool. DTC P0069 5A should not set.
Note: The vehicle used for the comparison is not limited to the same type of vehicle being serviced. A vehicle known to provide an accurate reading is acceptable.
- Compare the scan tool MAP sensor pressure parameter, and the scan tool BARO sensor pressure parameter, to the pressure parameter of a known good vehicle. Both readings should be within 3 kPa (0.44 PSI) of the known good vehicle.
Note: The Altitude vs. Barometric Pressure table indicates a pressure range for a given altitude under normal weather conditions. Weather conditions consisting of very low or very high pressure and/or very low or very high temperature may cause a reading to be slightly out of range.
- Compare the scan tool MAP sensor pressure parameter, and the scan tool BARO sensor pressure parameter, to the reading in the Altitude Versus Barometric Pressure table. Both parameters should be within the specified range indicated on the table.
- Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
Circuit/System Testing
- Ignition ON, compare the scan tool BARO pressure sensor parameter to the reading in the Altitude Versus Barometric Pressure table.
⇒ | If not within the specified range, refer to DTC P0105 for further diagnosis. |
- Ignition OFF, disconnect the harness connector at the B65 Intake Manifold Pressure and Air Temperature Sensor.
- Test for less than 5 Ω between the low reference circuit terminal 4 and ground.
⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module. |
- Ignition ON, test for 4.8-5.2 V between the 5-volt reference circuit terminal 2 and ground.
⇒ | If less than the specified range, test the 5-volt reference circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module. |
⇒ | If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module. |
- Verify the scan tool Boost Pressure Sensor parameter is less than 20 kPa (2.9 PSI).
⇒ | If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module. |
- Install a 3 A fused jumper wire between the signal circuit terminal 1 and the 5-volt reference circuit terminal 2. Verify the Boost Pressure Sensor parameter is between 40-45 kPa (5.8-6.5 PSI).
⇒ | If less than the specified range, test the signal circuit for an open or a short to ground. If the circuit tests normal, replace the K20 Engine Control Module. |
⇒ | If greater than the specified range, test the signal circuit for a high resistance. If the circuit tests normal, replace the K20 Engine Control Module. |
- If all circuits test normal, test or replace the B65 Intake Manifold Pressure and Air Temperature Sensor.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
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