DTC P0651 Without RPO CTF
Circuit Description
The engine control module (ECM) provides 5 volts for the accelerator pedal position (APP) sensor 2.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
| • | The circuit voltage is more than 5.5 volts. |
| • | The circuit voltage is less than 4.5 volts. |
| • | The above conditions are met for 0.7 seconds. |
Action Taken When the DTC Sets
The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | Clear the MIL and the DTC with a scan tool. |
Diagnostic Aids
Inspect for the following conditions:
| • | A poor connection at the ECM connector |
| • | A poor connection at the battery connector |
| • | A harness short |
| • | A defect at the sensor |
Step | Action | Values | Yes | No | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics | ||||||||||||
1 | Did you perform the Diagnostic System Check-Engine Controls? | -- | Go to Step 2 | |||||||||
2 |
Does the scan tool display the DTC? | -- | Go to Step 3 | Go to Intermittent Conditions | ||||||||
3 |
Does the voltage measure within the specified range? | 4.5-5.5 V | Go to Step 4 | Go to Step 6 | ||||||||
4 |
Does the resistance of the APP 2 sensor change while moving the accelerator pedal? | -- | Go to Step 6 | Go to Step 5 | ||||||||
5 | Replace the APP sensor. Did you complete the replacement? | -- | Go to Step 8 | -- | ||||||||
6 | Inspect for the following conditions:
Did you find and correct the condition? | -- | Go to Step 8 | Go to Step 7 | ||||||||
7 | Replace the ECM. Did you complete the replacement? | -- | Go to Step 8 | -- | ||||||||
8 |
Does the DTC run and pass? | -- | Go to Step 9 | Go to Step 2 | ||||||||
9 | Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? | -- | System OK | |||||||||
DTC P0651 With RPO CTF
Circuit Description
The engine control module (ECM) provides 5-volt reference voltage through the reference circuit 2 to the accelerator pedal position sensor. The ECM monitors the voltage on the 5-volt reference 2 circuit. If the ECM detects that the voltage is out of tolerance, this DTC will set.
Conditions for Running the DTC
| • | The ignition switch is ON. |
| • | The battery voltage is between 10-16 volts. |
Conditions for Setting the DTC
When the 5-volt reference circuit 2 voltage is more than 5.5 volts or less than 4.5 volts.
Action Taken When the DTC Sets
| • | The ECM illuminates the malfunction indicator lamp (MIL) and reduced engine power indicator lamp, if fitted, when the diagnostic runs and fails. |
| • | The ECM records the operating conditions at the time the diagnostic fails. The ECM stores this information in the Failure Records. |
Conditions for Clearing the DTC
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | Clear the MIL and the DTC with a scan tool. |
Diagnostic Aids
If an intermittent condition is suspected, the following may cause an intermittent:
| • | Poor connections |
| • | Misrouted harness |
| • | Rubbed through wire insulation |
| • | Broken wire inside the insulation |
Inspect for the following conditions:
| • | Poor connection at ECM--Inspect harness connectors for backed-out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection. |
| • | Damaged harness--Inspect the wiring harness for damage. If the harness appears to be OK, observe the DTC P0651 display on the scan tool while moving the connectors and wiring harness related to the sensor. A change in the display will indicate the location of the fault. |
Step | Action | Values | Yes | No | ||||
|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics | ||||||||
1 | Did you perform the Diagnostic System Check - Engine Controls? | -- | Go to Step 2 | |||||
2 |
Does the DTC fail this ignition? | -- | Go to Step 3 | Go to Diagnostic Aids | ||||
3 |
Is the APP Sensor 2 parameter within the specified range? | 4.5-5.5 V | Go to Step 5 | Go to Step 4 | ||||
4 |
Did you find and correct the condition? | -- | Go to Step 8 | Go to Step 6 | ||||
5 | Replace the APP sensor. Refer to Accelerator Pedal Position Sensor Replacement . Did you complete the replacement? | -- | Go to Step 8 | -- | ||||
6 |
Did you find and correct the condition? | -- | Go to Step 8 | Go to Step 7 | ||||
7 |
Important: The replacement ECM must be programmed. Replace the ECM. Refer to Engine Control Module Replacement/Restore Fuel Rate Data . Did you complete the replacement? | -- | Go to Step 8 | -- | ||||
8 |
Did the DTC fail this ignition? | -- | Go to Step 2 | Go to Step 9 | ||||
9 | Observe the stored information, Capture Info with a scan tool. Are there any DTCs that you have not diagnosed? | -- | System OK | |||||
