DTC P2125

Circuit Description

The accelerator pedal position (APP) sensor 2 is a potentiometer type sensor with the following 3 circuits:

A 5-volt reference circuit
A low reference circuit
A signal circuit

The control module provides the APP sensor a 5-volt reference circuit and a low reference circuit. The APP sensor then provides the control module a signal voltage proportional to pedal movement. The APP sensor 2 signal voltage is low at rest and increases as the pedal is depressed. When the control module detects that the APP sensor 2 signal or the APP sensor 5-volt reference voltage is outside the predetermined range, DTC P2125 sets.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P2125 Accelerator Pedal Position (APP) Sensor 2 Circuit

Conditions for Running the DTC

DTC P2107 is not set.
The ignition is ON.
The ignition voltage is more than 5.23 volts.

Conditions for Setting the DTC

The APP sensor 2 voltage is less than 0.235 volt or more than 4.487 volts. OR
The APP sensor 2 5-volt reference voltage is less than 4.54 volts or more than 5.21 volts.

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.
The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records.
The driver information center, if equipped, may display a message.

Conditions for Clearing the DTC

A current DTC Last Test Failed clears when the diagnostic runs and passes.
A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
Clear the DTC with a scan tool.

Step	Action	Values	Yes	No
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module (PCM) Connector End Views and Engine Controls Connector End Views
1	Did you perform the Diagnostic System Check - Vehicle?	--	Go to Step 2	Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
2	Turn ON the ignition, with the engine OFF. Observe the accelerator pedal position (APP) sensor 2 voltage with the accelerator pedal in the rest position with a scan tool. Is the voltage within the specified range?	0.24-2 V	Go to Step 4	Go to Step 3
3	Turn OFF the ignition. Disconnect the APP harness connector. Turn ON the ignition, with the engine OFF. Measure the voltage of the APP sensor reference circuit with a DMM. Is the voltage within the specified range?	4.8-5.2 V	Go to Step 6	Go to Step 9
4	Is DTC P2138 also set?	--	Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information	Go to Step 5
5	Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records. Did the DTC fail this ignition?	--	Go to Step 6	Go to Intermittent Conditions
6	Turn OFF the ignition. Disconnect the accelerator pedal harness connector. Turn ON the ignition, with the engine OFF. Observe the APP sensor 2 voltage parameter with a scan tool. Is the voltage within the specified range?	0-0.2 V	Go to Step 7	Go to Step 11
7	Connect a fused jumper wire between the APP sensor 2 5-volt reference circuit and the APP sensor 2 signal circuit at the accelerator pedal harness connector. Observe the APP sensor 2 voltage parameter with a scan tool. Does the scan tool indicate the APP sensor 2 voltage is within the specified range?	4.6-5.2 V	Go to Step 13	Go to Step 8
8	Turn OFF the ignition. Remove the fused jumper. Turn ON the ignition, with the engine OFF. Measure the voltage of the APP sensor 5-volt reference circuit with a DMM. Is the voltage within the specified range?	4.6-5.2 V	Go to Step 10	Go to Step 9
9	Does the DMM indicate voltage less than the specified value on the APP sensor 2 5-volt reference circuit?	5 V	Go to Step 14	Go to Step 16
10	Test the APP sensor 2 signal circuit for an open or for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition?	--	Go to Step 22	Go to Step 12
11	Test the APP sensor 2 signal circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition?	--	Go to Step 22	Go to Step 19
12	Test the APP sensor 2 signal circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition?	--	Go to Step 22	Go to Step 19
13	Test the APP sensor 2 low reference circuit for an open or for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition?	--	Go to Step 22	Go to Step 17
14	Test the APP sensor 2 5-volt reference circuit for an open or for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition?	--	Go to Step 22	Go to Step 15
15	Test the APP sensor 2 5-volt reference circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition?	--	Go to Step 22	Go to Step 19
16	Test the APP sensor 2 5-volt reference circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition?	--	Go to Step 22	Go to Step 19
17	Is DTC U0107 also set?	--	Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information	Go to Step 18
18	Test for an intermittent and for a poor connection at the accelerator pedal harness connector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition?	--	Go to Step 22	Go to Step 20
19	Test for an intermittent and for a poor connection at the throttle body harness connector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition?	--	Go to Step 22	Go to Step 21
20	Replace the accelerator pedal assembly. Refer to Accelerator Controls Pedal Replacement . Did you complete the replacement?	--	Go to Step 22	--
21	Replace the throttle body assembly. Refer to Throttle Body Assembly Replacement . Did you complete the replacement?	--	Go to Step 22	--
22	Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records. Did the DTC fail this ignition?	--	Go to Step 2	Go to Step 23
23	Important Be aware that repairing one individual condition may correct more than one DTC. Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?	--	Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information	System OK