DTC P1273 Without RPO CTF
| Table 1: | APP Sensor Position Table |
| Table 2: | DTC P1273 APP sensor 1-3 correlation |
Circuit Description
The accelerator pedal position (APP) sensor is mounted on the accelerator pedal control assembly. The sensor is made up of 3 individual sensors within one housing. Three separate signal, low reference, and 5-volt reference circuits are used in order to interface the APP sensor with the engine control module (ECM). Each sensor has a unique functionality to determine pedal position as shown in the table below. The ECM uses the APP sensor to determine the amount of acceleration or deceleration desired by the person driving the vehicle via fuel injector control. This DTC sets if the ECM determines an out of range condition with the APP sensor.
APP Sensor | Actual Pedal Position | % Depressed as Observed on a Scan Tool | Voltage as Observed on a Scan Tool |
|---|---|---|---|
1 | Pedal at rest | 0 | .52 - .80 |
1 | Pedal at full travel | 100 | 2.12 - 2.78 |
2 | Pedal at rest | 0 | 4.25 - 4.53 |
2 | Pedal at full travel | 100 | 2.24 - 2.93 |
3 | Pedal at rest | 0 | 3.95 - 4.13 |
3 | Pedal at full travel | 100 | 2.69 - 3.16 |
Conditions for Running the DTC
| • | DTCs P1277, P1278, P1287, P1288, P0641, or P0651 are not set. |
| • | The ignition switch is in the crank or run position. |
| • | The ignition voltage is between 7-16 volts. |
Conditions for Setting the DTC
| • | APP sensor 1 and APP sensor 3 are more than 10 percent out of range of each other. |
| • | All of the above conditions present for less than 1 second. |
Action Taken When the DTC Sets
| • | The control module stores the DTC information into memory when the diagnostic runs and fails. |
| • | The malfunction indicator lamp (MIL) will not illuminate. |
| • | If one or more APP sensor DTCs are set for a single APP sensor, the control module will use the remaining two APP sensors to calculate throttle response. |
| • | If certain multiple APP sensor DTCs are set for more than one APP sensor, the following occurs: |
| - | The control module commands Reduced Engine Power mode. |
| - | The APP indicated angle is limited to a predetermined value to limit the amount of throttle control. |
| • | If all three APP sensors are out of range, the APP indicated angle is limited to 0 percent. The control module only allows the engine to idle. |
Conditions for Clearing the DTC
| • | A current DTC Last Test Failed clears when the diagnostic runs and passes. |
| • | Clear the DTC with a scan tool. |
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Engine Controls Schematics | |||
1 | Did you perform the Diagnostic System Check-Engine Controls? | Go to Step 2 | |
2 | Is DTC P1271 also set? | Go to DTC P1271 | Go to Step 3 |
3 | Is DTC P1272 also set? | Go to DTC P1272 | -- |
DTC P1273 With RPO CTF
| Table 1: | APP Sensor Position Table |
Circuit Description
The accelerator pedal position (APP) sensor is mounted on the accelerator pedal assembly. The sensor is made up of 3 individual sensors within 1 housing.
The accelerator pedal position sensor 1, sensor 2, and sensor 3 are potentiometer type sensors, each with the following circuits:
| • | A 5-volt reference circuit |
| • | A low reference circuit |
| • | A signal circuit |
The engine control module (ECM) provides the APP sensors a 5-volt reference circuit and a low reference circuit. The APP sensors then provide the ECM signal voltages proportional to pedal movement. The APP sensor 1 signal voltage is low at rest and increases as the pedal is depressed. The APP sensor 2 signal voltage is high at rest and decreases as the pedal is depressed. The APP sensor 3 signal voltage is high at rest and decreases as the pedal is depressed.
When the ECM detects that the APP sensor 1 signal and the APP sensor 3 signal circuits are out of the correlation, DTC will set.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
The APP sensor 1 and APP sensor 3 are more than 10 percent out of range of each other.
Action Taken When the DTC Sets
| • | The ECM illuminates the malfunction indicator lamp (MIL) 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. |
| • | If all 3 APP sensors are out of range, the APP indicated angle is limited to 0 percent. The ECM only allows the engine to idle. |
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. |
APP Sensor | Actual Pedal Position | % Depressed as Observed on a Scan Tool | Voltage as Observed on a Scan Tool |
|---|---|---|---|
1 | Pedal at rest | 0 | 0.52-0.80 |
1 | Pedal at full travel | 100 | 2.38-2.66 |
2 | Pedal at rest | 0 | 4.20-4.48 |
2 | Pedal at full travel | 100 | 2.34-2.62 |
3 | Pedal at rest | 0 | 3.92-4.09 |
3 | Pedal at full travel | 100 | 2.79-2.96 |
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 5 | Go to Step 3 |
3 |
Does the DTC fail this ignition? | -- | Go to Step 4 | Go to Intermittent Conditions |
4 | Is DTC P0641, P0651, P1646, P1282 or P1283 also set? | -- | Go to Step 5 | |
5 | Is DTC P1271 also set? | -- | Go to DTC P1271 | Go to Step 6 |
6 | Is DTC P1272 also set? | -- | Go to DTC P1272 | Go to Step 7 |
7 |
Did the DTC fail this ignition? | -- | Go to Step 2 | Go to Step 8 |
8 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | -- | System OK | |
