Circuit/System Verification
WARNING: This page is about a different car, the 2017 GMC Acadia. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition » On / Vehicle » In Service Mode
- Verify DTC P0641, P0651, P0697, P06A3 is not set.
- If any of the DTCs are set
- If none of the DTCs are set
- If you were sent here from DTC P0101, P0121, P1101 » Refer to Circuit/System Testing.
- Verify the scan tool parameter:Throttle Body Idle Air Flow Compensation =Less than 90 %
- If 90 % or greater
- If less than 90 %
- Perform the scan tool control function:Throttle Sweep
Verify the scan tool parameter:Throttle Position Sensors 1 and 2<=Agree
- If the parameter does not display the following:Agree
Refer to:DTC P0121-P0123, P0222, P0223, P16A0-P16A2, or P2135
- If the parameter displays the following:Agree
- If the parameter does not display the following:Agree
- Determine the current vehicle testing altitude.
- Verify the scan tool parameter:MAP Sensor =The value should be within the range listed in the table: Altitude Versus Barometric Pressure
- If not in the specified range
Refer to: Circuit/System Testing
- If in the specified range
- If not in the specified range
- Engine » Idling - At normal operating temperature
- All accessories Off.
- Verify the scan tool parameter:MAP Sensor = 26 to 52 kPa (3.8 to 7.6 PSI) and changes
- If not between 26 to 52 kPa (3.8 to 7.6 PSI) or does not change
Refer to: Circuit/System Testing
- If between 26 to 52 kPa (3.8 to 7.6 PSI) and changes
- If not between 26 to 52 kPa (3.8 to 7.6 PSI) or does not change
- Observe the following scan tool parameter:MAF Sensor & Engine Speed.
- Increase the engine speed slowly to 3, 000 RPM and then back to idle.
- Verify the scan tool parameter:MAF Sensor =The value should change smoothly and gradually as the engine speed is increased and decreased.
- If the value does not change smoothly and gradually
Refer to:DTC P0101
- If the value changes smoothly and gradually
- If the value does not change smoothly and gradually
- Verify the scan tool parameter:MAP Sensor =The value should not spike or drop out.
Perform the action while monitoring the parameter:
- Wiggle the harness and connector:B74 Manifold Absolute Pressure Sensor
- Wiggle the harness and connector:K20 Engine Control Module
- If the value spikes or drops out
Repair as necessary » Wiring / Terminal(s) / Electrical Connector(s)
- If the value does not spike or drop out
- Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
- Verify the DTC does not set.
- If the DTC sets
Refer to: Circuit/System Testing
- If the DTC is not set
- If the DTC sets
- All OK.