PRE-RELEASE
DTC P0068 or P1101
| DTC P0068 or P1101 |
| Diagnostic Instructions |
| • |
Perform the
Diagnostic System Check - Vehicle
prior to using this diagnostic procedure.
|
|
| • |
Review
Strategy Based Diagnosis
for an overview of the diagnostic approach.
|
|
| • |
Diagnostic Procedure Instructions
provides an overview of each diagnostic category.
|
|
| DTC Descriptor |
DTC P0068
Throttle Body Airflow Performance
DTC P1101
Intake Air Flow System Performance
| Circuit/System Description |
The engine control module (ECM) compares actual airflow based on throttle position (TP) to a calculated airflow based on manifold absolute pressure (MAP) sensor, and mass air flow (MAF).
| Conditions for Running the DTC |
DTC P0068
| • |
The engine speed is greater than 800 RPM.
|
|
| • |
The ignition voltage is greater than 6.0 volts.
|
|
| • |
The throttle actuator control system is not in reduced power mode.
|
|
| • |
The DTC runs continuously when the above conditions are met.
|
|
DTC P1101
| • |
DTCs P0096, P0097, P0098, P0102, P0103, P0107, P0108, P0111, P0112, P0113, P0016, P0117, P0118, P0119, P0128, P0236, P0237, P0238, P0335, P0336, P0401, P0405, P0406, P042E, P2227, P2228, P2229, or P2230 are not set
|
|
| • |
The engine speed is between 400-6,000 RPM
|
|
| • |
The ECT Sensor is between -7 and +125°C (+19 and +257°F).
|
|
| • |
The IAT 1 Sensor is between -20 and +125°C (-4 and +257°F).
|
|
| • |
The DTC runs continuously when the above conditions are met.
|
|
| Conditions for Setting the DTC |
The ECM detects that the actual airflow rate is greater than the calculated airflow.
| Action Taken When the DTC Sets |
P0068
| • |
DTC P0068 is a Type A DTC.
|
|
| • |
The control module commands the throttle actuator control (TAC) system to operate in the Reduced Engine Power mode.
|
|
| • |
A message center or an indicator displays Reduced Engine Power.
|
|
| • |
Under certain conditions the control module commands the engine OFF.
|
|
P1101
DTC P1101 is a Type B DTC.| Conditions for Clearing the DTC |
| • |
DTC P0068 is a Type A DTC.
|
|
| • |
DTC P1101 is a Type B DTC.
|
|
| Diagnostic Aids |
| • |
Inspect for a condition in which the throttle valve may have been held open. For example, ice may have formed in the throttle bore causing the throttle valve not to close.
|
|
| • |
Certain aftermarket air filters may cause a DTC to set.
|
|
| • |
Certain aftermarket air induction systems may cause a DTC to set.
|
|
| • |
Certain aftermarket air induction systems may cause a DTC to set.
|
|
| • |
A high resistance condition on the throttle position and throttle actuator control circuits could cause a DTC to set.
|
|
| • |
An inaccurate MAF sensor, an intake air flow restriction, any unmetered air that enters the engine downstream of the MAF sensor, or an air induction leak may cause a DTC to set.
|
|
| • |
A low battery condition may cause a DTC to set.
|
|
| Reference Information |
Schematic Reference
Engine Controls Schematics
Connector End View Reference
Component Connector End Views
Electrical Information Reference
| • |
Circuit Testing
|
|
| • |
Connector Repairs
|
|
| • |
Testing for Intermittent Conditions and Poor Connections
|
|
| • |
Wiring Repairs
|
|
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
| Circuit/System Testing |
| 1. |
Inspect for the following conditions:
|
|
| • |
The air intake duct system for loose clamps, cracks, any type of leak, or other damage
|
| • |
The air intake duct system for being collapsed or any type of restriction
|
| • |
Whether the mass airflow sensor is correctly mounted The arrow shows the direction of airflow and specifies how the hose tabs and sensor grooves shall be aligned. Refer to
Mass Airflow Sensor Replacement
.
|
| • |
Restricted air filter
|
| • |
Throttle body for dirt, debris, and coking-Refer to
Throttle Body Cleaning
.
|
| • |
A damaged throttle body blade or shaft
|
| • |
Splits, kinks, or improper connections at the vacuum hoses
|
| • |
Missing, restricted, or leaking exhaust components-Refer to
Fastener Tightening Specifications
.
|
| • |
Vacuum leaks at the intake manifold, throttle body, and injector O-rings
|
| 2. |
If a condition exists, repair as necessary.
|
|
| 3. |
Ignition ON, observe the diagnostic trouble code (DTC) information with a scan tool. Verify that no other DTCs are not set.
|
|
| 4. |
If any other DTCs are set, refer to
Diagnostic Trouble Code (DTC) List - Vehicle
for further diagnosis.
|
|
| 5. |
Determine the current vehicle testing altitude. Compare the MAP sensor pressure parameter with the value in the
Altitude Versus Barometric Pressure
table. The MAP sensor pressure parameter should be within the specific range specified in the table.
|
|
| 6. |
If the MAP sensor pressure is not within the range specified for your altitude, refer to
Diagnostic Trouble Code (DTC) List - Vehicle
for P0106.
|
|
| 7. |
Engine idling, observe the MAP Sensor parameter. The reading should be between 26-52 kPa.
|
|
| 8. |
If not within the specified range, refer to
Diagnostic Trouble Code (DTC) List - Vehicle
for P0106.
|
|
| 9. |
Idle the engine. Observe the MAP Sensor kPa parameter with a scan tool. Slowly increase the engine speed and then reduce back to idle. The MAP sensor kPa should change smoothly and gradually while the engine speed increases and then returns to idle.
|
|
| 10. |
If the MAP sensor kPa does not change, refer to
Diagnostic Trouble Code (DTC) List - Vehicle
for P0106.
|
|
| 11. |
Perform the Throttle Sweep Test while observing the TAC Motor parameter with a scan tool. The TAC Motor parameter should display Enabled while the Throttle Sweep Test is in progress. |
|||||||
| 12. |
If not the specified value, replace the throttle body assembly. |
|||||||
| 13. |
Inspect the throttle body for the following conditions:
|
|
| • |
Loose or damaged throttle blade
|
| • |
Broken throttle shaft
|
| • |
Any throttle body damage
|
| 14. |
If any of these conditions exist, replace the throttle body assembly.
|
|
| 15. |
Use the scan tool snapshot function to take a snapshot of the engine data list while performing the actions listed below.
|
|
| 15.1. |
Engine idling
|
| 15.2. |
Increase the engine speed slowly to 3,000 RPM and then back to idle.
|
| 15.3. |
Exit from the scan tool snapshot and review the data.
|
| 15.4. |
Read off the mass airflow sensor, data block by data block, with the scan tool. The MAF sensor g/s parameter should change smoothly and gradually while the engine speed increases and then returns to idle.
|
| 16. |
If the MAF sensor g/s does not change smoothly and gradually, replace the B75B MAF/IAT sensor.
|
|
| 17. |
If all conditions test normal, test the engine for a mechanical condition. Refer to
Symptoms - Engine Mechanical
.
|
|
| Repair Instructions |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • |
Mass Airflow Sensor Replacement
|
|
| • |
Throttle Body Assembly Replacement
|
|
| • |
Air Cleaner Element Replacement
|
|
