P0069
DTC P0069
DTC Descriptor
DTC P0069
- Manifold Absolute Pressure-Barometric Pressure Correlation
Diagnostic Fault Information
Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
Typical Scan Tool Data
Circuit/System Description
The barometric pressure (BARO) sensor is a transducer that varies resistance according to changes in altitude and atmospheric conditions. This gives the control module an indication the current of barometric pressure. The control module uses this information to calculate fuel delivery. The BARO sensor has a 5-volt reference circuit, a low reference circuit, and a signal circuit. The control module supplies 5 volts to the BARO sensor on a 5-volt reference circuit, and provides a ground on a low reference circuit. The BARO sensor provides a voltage signal to the control module on a signal circuit relative to the pressure changes. The control module compares the BARO sensor to the manifold absolute pressure (MAP) sensor in order to monitor the BARO sensor operation.
Conditions for Running the DTC
* DTCs P0068, P0101, P0102, P0103, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0125, P0128, P0220, P0502, P0503, P2135, P2227, P2228, P2229 are not set.
* The ignition is ON.
Conditions for Setting the DTC
* The control module detects that the difference between the BARO sensor pressure and the MAP sensor pressure is more than 5 kPa when the ignition is ON before engine startup.
OR
* The difference between the BARO sensor pressure and the control module predicted BARO is more than 60 kPa when the engine is running.
* The above conditions are met for 1 second.
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
Verify that any electrical aftermarket devices are properly connected and grounded. Refer to Checking Aftermarket Accessories in Diagnostic Aids. Component Tests and General Diagnostics
Circuit/System Verification
If DTCs P0106, P0107, P0108, P0641, P0651, or P2227, P2228, P2229 are also set, refer to Diagnostic Trouble Code (DTC) List - Vehicle for further information. Diagnostic Trouble Code Descriptions
Circuit/System Testing
1. Determine the altitude for your area. Refer to Altitude Versus Barometric Pressure. Both sensor values should be within 5 kPa of each other and the Altitude vs. Barometric Pressure table.
2. Ignition ON, determine which sensor is out of range by comparing MAP and BARO Sensors kPa parameters with a scan tool.
3. Ignition OFF, disconnect the harness connector at the affected sensor.
4. Ignition OFF, allow sufficient time for the control module to power down. Test for less than 5 ohms of resistance between the low reference circuit terminal 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 ECM.
5. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal and ground.
^ If less than the specified range, test the 5-volt 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-volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.
6. Verify the scan tool sensor parameter is less than 12 kPa.
^ If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the ECM.
7. Install a 3-amp fused jumper wire between the signal circuit and the low reference circuit. Verify the scan tool sensor parameter is greater than 103 kPa for MAP and 126 kPa for BARO.
^ If less than the specified range, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
8. If all circuits test normal, test or replace the affected sensor.
Component Testing
Important: You must perform the Circuit/System Testing before proceeding with the Component Test.
1. Turn ON the ignition with the engine OFF and remove the affected sensor.
2. Install a 3-amp fused jumper wire between the 5-volt reference terminal C of the sensor and 5-volt reference.
3. Install a jumper wire between the low reference terminal of the sensor and ground.
4. Install a jumper wire at the signal terminal sensor.
5. Connect a DMM between the jumper wire from terminal of the sensor and ground.
6. Install the J 23738-A to the sensor vacuum port. Slowly apply vacuum to the sensor while monitoring the voltage on the DMM. The voltage should vary between 5.2-0 volts without any spikes or dropouts.
^ If the voltage is not within the specified range or is erratic, replace the affected sensor.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests
* Programming and Relearning Programming and Relearning
* Barometric Pressure Sensor Replacement
* Manifold Absolute Pressure Sensor Replacement