P0106

P0106-MANIFOLD ABSOLUTE PRESSURE SENSOR PERFORMANCE





For a complete wiring diagram Refer to Diagrams/Electrical.

Theory of Operation


The boost pressure sensor is used to measure exhaust gas pressure in the intake manifold. The Electronic Control Module (ECM) provides a 5-volt supply to the intake manifold pressure sensor on the sensor supply circuit. The ECM also provides a ground on the sensor return circuit. The boost pressure sensor provides a signal to the ECM on the boost pressure sensor signal circuit. This sensor signal voltage changes based on the pressure in the intake manifold. The ECM will detect a low signal voltage at operating conditions such as during an idle or a deceleration. The ECM will detect a high signal voltage during high engine load operating conditions. There are two parts to this fault code, a key on check and a rationality check. At key ON, the readings for the boost pressure, exhaust gas pressure, and barometric pressure are compared. This fault code occurs if the boost pressure reading is different from the other two. This diagnostic is run 5 seconds after key on. During normal engine operation, other air handling sensor values are used to estimate a boost pressure. If the difference between the value read from the boost pressure sensor and the estimation is above a calibrated threshold for a calibrated period of time then an error is recorded. The key-on portion of the rationality will light the MIL immediately after the diagnostic runs and fails. The rationality portion has to fail in two consecutive drive cycles for the MIL to become illuminated. The ETC lamp will also be illuminated. During this time the ECM uses an estimated boost pressure. The ECM turns off the MIL when the diagnostic runs and passes in 4 consecutive drive cycles.

- When Monitored:
While the key is on.

- Set Condition:
The boost pressure recorded at key on is not within a calibrated range from the inlet air pressure sensor.







Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Initial Inspection and Diagnostic Overview


1. EGR AIRFLOW THROTTLE CONTROL VALVE
Remove the boot from the EGR airflow throttle control valve.
Using a mirror, look at the butterfly valve on the inside of the EGR airflow throttle control valve.
Start the vehicle, let idle for 10 seconds and key off.

NOTE: If functioning properly the EGR airflow throttle control valve will cycle closed immediately after the engine is shut down.

Did the EGR airflow throttle control valve cycle closed immediately after the engine was shut down?

Yes


- Go To 2


No


- Replace the EGR airflow throttle control valve.
- Perform POWERTRAIN VERIFICATION TEST (DIESEL). Powertrain Verification Test



2. BOOST PRESSURE SENSOR
Turn ignition switch on. Wait 5 seconds after ignition switch is turned on.
Using the scan tool, read DTC's
Is P0106 stored?

Yes


- Go To 3


No


- Replace the Boost Pressure sensor.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test



3. BOOST PRESSURE SENSOR
Erase the DTC with the scan tool.
Start the engine and let it idle for 1 minute.
With the scan tool, monitor the boost pressure reading.
Does the value fluctuate slightly, indicating the sensor is not stuck?

Yes


- Repair complete
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test


No


- Replace the Boost pressure sensor.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test