Subject: | Engine Power Reduced or Starting Disabled Service Throttle |
Models: | 2006- 2007 Buick Lucerne and Cadillac DTS |
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
A customer may comment about one or more of the following concerns. These concerns may be intermittent:
• | Malfunction Indicator Lamp (MIL)/ Check Engine Light is illuminated |
• | ENGINE POWER REDUCED or STARTING DISABLED SERVICE THROTTLE messages displayed on the Driver Information Center (DIC) |
• | The engine will not start |
One or more of the following DTC may be stored:
P0452 | Fuel Tank Pressure (FTP) Sensor Circuit Low Voltage |
P0650 | Malfunction Indicator Lamp (MIL) Control Circuit |
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 |
Open and inspect C111 Body Harness to the Engine Harness for poor connections. Gently tug on each wire going into and out of the connector to ensure each terminal is locked into the connector, and that the terminals are not pushing out when the connector is closed and the lever is locked. C111 is located on the LF Strut Tower in the Engine Compartment.
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.