The accelerator pedal position (APP) sensor is mounted on the accelerator pedal control assembly. The sensor is made up of three individual sensors within one housing. The engine control module (ECM) uses the APP sensors to determine the amount of acceleration or deceleration desired by the person driving the vehicle via the fuel injector control. The APP sensor 2 has the following circuits:
• | A 5-volt reference circuit |
• | A low reference circuit |
• | APP sensor 2 signal circuit |
The ECM supplies 5 volts to the APP sensor 2 on the 5-volt reference circuit. The ECM also provides a ground on the low reference circuit. The APP sensor 2 provides a signal to the ECM on the APP sensor 2 signal circuit which is relative to the position changes of the accelerator pedal angle. The ECM monitors the APP sensor 2 signal for voltage outside the normal range of the APP sensor 2. If the ECM detects an excessively high APP sensor 2 signal voltage, this DTC will set.
This diagnostic procedure supports the following DTC:
DTC P1283 Accelerator Pedal Position (APP) Sensor 2 Circuit High Voltage
The ignition switch is ON.
The APP sensor 2 voltage is more than 4.75 volts.
• | The ECM does not illuminate the malfunction indicator lamp (MIL) when the diagnostic runs and tails. |
• | The ECM records the operating conditions at the time the diagnostic fails. The ECM stores this information in the Failure Records. |
• | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
• | Clear the DTC with a scan tool. |
Step | Action | Values | Yes | No |
---|---|---|---|---|
Schematic Reference: Engine Controls Schematics | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |
2 |
Is the APP sensor 2 parameter more than the specified value? | 4.75 V | Go to Step 4 | Go to Step 3 |
3 |
Did the DTC fail this ignition? | -- | Go to Step 4 | Go to Intermittent Conditions |
4 |
Is DTC P0651 also set? | -- | Go to Step 5 | Go to Step 8 |
5 |
Is the APP sensor 2 parameter less than the specified value? | 0.25 V | Go to DTC P0651 | Go to Step 8 |
6 |
Is the APP sensor 2 parameter more than the specified value? | 4.75 V | Go to Step 8 | Go to Step 7 |
7 |
Is the DMM voltage within the specified range? | 4.5-5.5 V | Go to Step 8 | Go to Step 9 |
8 |
Important: The APP sensor 2 may be damaged if the circuit short to voltage source.
Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 10 |
9 |
Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 11 |
10 |
Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 12 |
11 |
Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 13 |
12 | Replace the APP sensor. Refer to Accelerator Pedal Position Sensor Replacement . Did you complete the replacement? | -- | Go to Step 14 | -- |
13 |
Important: The replacement ECM must be programmed. Replace the ECM. Refer to Engine Control Module Programming and Setup , Engine Control Module Replacement/Restore Fuel Rate Data , and Fuel Injector Flow Rate Programming . Did you complete the replacement? | -- | Go to Step 14 | -- |
14 |
Did the DTC fail this ignition? | -- | Go to Step 2 | Go to Step 15 |
15 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | -- | System OK |