| Subject: | Starter Noise/Unwanted Engagement, No Start, SES, Reduced Power, A/C Inop |
| Models: | 2008 Buick Lucerne w/ V6 Engine |
This PI was superceded to update the CONDITION/ CONCERN field to include "hesitation" and DTC p2101, p2120, and p2125 were added to the list of potential concerns. Please discard PIC4882.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
A customer may comment they experience one or more of the following concerns.
| • | Reduced Power Message on the Driver Information Center (DIC) |
| • | Starter engages while the engine is already running |
| • | Noise from the engine compartment |
| | Inspection of the vehicle may reveal one or more fuses in the underhood fuse block listed below are open. |
| | One or more of the following DTC may be stored. |
| • | P0103 Mass Air Flow (MAF) Sensor Circuit High Frequency |
| • | P0106 Manifold Absolute Pressure (MAP) Sensor Performance |
| • | P0107 Manifold Absolute Pressure (MAP) Sensor Circuit Low Voltage |
| • | P0108 Manifold Absolute Pressure (MAP) Sensor Circuit High Voltage |
| • | P0116 Engine Coolant Temperature (ECT) Sensor Performance. |
| • | P0117 Engine Coolant Temperature (ECT) Sensor Circuit Low Voltage |
| • | P0335 Crankshaft Position (CKP) Sensor A Circuit |
| • | P0340 Camshaft Position (CMP) Sensor Circuit |
| • | P0341 Camshaft Position (CMP) Sensor Performance |
| • | P0350 Ignition Coil Control Circuit |
| • | P0443 Evaporative Emission (EVAP) Purge Solenoid Control Circuit |
| • | P0615 Starter Relay Control Circuit |
| • | P0641 5-Volt Reference 1 Circuit |
| • | P0645 Air Conditioning (A/C) Clutch Relay Control Circuit |
| • | P0973 1-2 Shift Solenoid (SS) Control Circuit Low Voltage |
| • | P0976 2-3 Shift Solenoid (SS) Control Circuit Low Voltage |
| • | P1111 Intake Air Temperature (IAT) Sensor Circuit Intermittent High Voltage |
| • | P1112 Intake Air Temperature (IAT) Sensor Circuit Intermittent High Voltage |
| • | P1125 Accelerator Pedal Position (APP) System |
| • | P1574 Stop Lamp Switch Circuit |
| • | P2101 Control Module Throttle Actuator Position Performance |
| • | P2107 Throttle Actuator Control (TAC) Module Internal Circuit |
| • | P2108 Throttle Actuator Control (TAC) Module Performance |
| • | P2119 Throttle Closed Position Performance |
| • | P2120 Accelerator Pedal Position (APP) Sensor 1 Circuit |
| • | P2122 Accelerator Pedal Position (APP) Sensor 1 Circuit Low Voltage |
| • | P2123 Accelerator Pedal Position (APP) Sensor 1 Circuit High Voltage |
| • | P2125 Accelerator Pedal Position (APP) Sensor 2 Circuit |
| • | P2127 Accelerator Pedal Position (APP) Sensor 2 Circuit Low Voltage |
| • | P2128 Accelerator Pedal Position (APP) Sensor 2 Circuit High Voltage |
| • | P2138 Accelerator Pedal Position (APP) Sensor 1-2 Correlation |
| • | P2162 Vehicle Speed Sensor (VSS) Circuit 1-2 Correlation |
| • | P2764 Torque Converter Clutch (TCC) Pressure Control (PC) Solenoid Control Circuit Low Voltage |
| • | U0121 Lost Communication With Electronic Brake Control Module (EBCM) |
| • | U1814 Powertrain High Speed Communication Enable Circuit |
The cause may be the engine wire harness chafing on the throttle body (1) when the intake manifold cover is installed.
Recommendation/Instructions:
Inspect the engine wire harness on top of the throttle body. Roll the harness over and check for gaps in the harness tape/ protection that can allow ckt 447 Starter Relay Coil Control to chafe. Repair the wiring as needed using procedures found in Diagnostic
Information and Procedures- Wiring Repairs.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
