DTC P0227 Accelerator Pedal Position (APP) Sensor 3 Circuit Low Voltage. Chevrolet Chevy P42 Commercial Chassis 1999

For 1990-2009 cars only

Makes 🢒 Chevrolet 🢒 1999 🢒 Chevy P42 Commercial Chassis 🢒 Engine 🢒 Engine Controls - 6.5L (L57) 🢒 DTC P0227 Accelerator Pedal Position (APP) Sensor 3 Circuit Low Voltage

Engine Controls Components L57 EFI
Engine Controls (Cell 22: Fuel Controls 5)
OBD II Symbol Description Notice
Handling ESD Sensitive Parts Notice
Handling ESD Sensitive Parts Notice

Circuit Description

The Accelerator Pedal Position (APP) module provides a voltage signal that changes relative to the accelerator pedal position. There are three sensors located within the APP module that are scaled differently.

Conditions for Running the DTC

The ignition switch in the on position.

Conditions for Setting the DTC

•	The voltage is less than 0.25 volts on the APP 3 sensor.

•	All diagnostic set conditions met for 2 seconds.

Action Taken When the DTC Sets

•	The Service Throttle Soon lamp will not illuminate when one APP DTC sets. The PCM will only illuminate the Service Throttle Soon lamp when multiple APP DTCs set.

•	The PCM records the operating conditions at the time the diagnostic fails. This information is stored in the Failure Record.

Conditions for Clearing the MIL/DTC

•	A History DTC will clear after forty consecutive warm-up cycles during which the diagnostic does not fail (the coolant temperature has risen 5°C (40°F) from the start up coolant temperature and the engine coolant temperature exceeds 71°C (160°F) during that same ignition cycle).

•	Use of a scan tool will clear the DTC codes.

Diagnostic Aids

There are no driveability issues associated with the APP module unless a DTC is present. The most likely cause of this DTC are poor connections or the sensor itself. The least likely is a PCM problem.

A scan tool reads the APP 3 position in volts. The scan tool should read about 4.0 volts with the throttle closed and the ignition ON or during idle. The voltage should decrease at steady rate as the throttle is moved toward a Wide Open Throttle (WOT). Also, 90% pedal travel is acceptable for a correct APP operation. Scan the APP 3 sensor while depressing the accelerator pedal with the engine stopped and the ignition ON. The display should vary from about 4.0 volts when the throttle is closed to about 2.0 volts when the throttle is held at Wide Open Throttle (WOT) position.

Test Description

Number(s) below refer to the step number(s) on the Diagnostic Table.

This step will determine if DTC P0227 is the result of a hard failure or an intermittent condition.

This step checks the PCM and wiring.

Step	Action	Value(s)	Yes	No
1	Important: Before clearing the DTCs, use the scan tool Capture Information function to save Freeze Frame and Failure records for reference. The control module's data is deleted once the scan tool Clear DTC Information function is used. Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?	--	Go to Step 2	Go to Powertrain On Board Diagnostic (OBD) System Check
2	Turn the ignition ON leaving the engine OFF. With the throttle closed, observe the APP 3 voltage on the Scan tool. Is the APP 3 voltage less than or equal to the specified value?	0.25 V	Go to Step 4	Go to Step 3
3	The DTC is intermittent. If no additional DTCs are stored, refer to Diagnostic Aids. If additional DTCs were stored, refer to those table(s) first. Are any additional DTCs stored?	--	Go to the Applicable DTC Table	Go to Diagnostic Aids
4	Disconnect the APP sensor electrical connector. Use the J 39200 , DMM, in order to probe the APP 3, 5 volt reference circuit at the APP harness. Is the voltage at the specified value?	5 V	Go to Step 5	Go to Step 6
5	Use J 39200 , DMM, in order to probe the APP 3 signal circuit at the APP harness. Is the voltage at the specified value?	4.8 V	Go to Step 10	Go to Step 8
6	Turn the ignition OFF. Disconnect the PCM and check the 5 volt reference circuit for an open or short to ground. If the 5 volt reference circuit is open or shorted to ground, repair it as necessary. Refer to Wiring Repairs. Did you perform a repair?	--	Go to Step 13	Go to Step 7
7	Check the 5 volt reference circuit for a proper connection at the PCM and replace terminal if necessary. Refer to Wiring Repairs. Did you perform a repair?	--	Go to Step 13	Go to Step 12
8	Turn the ignition OFF. Disconnect the PCM, and check the APP 3 signal circuit for an open, short to ground. If the APP 3 sensor signal circuit is open or shorted to ground, repair it as necessary. Refer to Wiring Repairs. Did you perform a repair?	--	Go to Step 13	Go to Step 9
9	Check the APP 3 sensor signal circuit for a proper connection at the PCM and replace the terminal if necessary. Refer to Wiring Repairs. Did you perform a repair?	--	Go to Step 13	Go to Step 12
10	Check for a proper electrical connection at the APP sensor. Refer to Wiring Repairs. Did you perform a repair?	--	Go to Step 13	Go to Step 11
11	Replace the APP module. Refer to Accelerator Pedal Position Module Replacement . Is the action complete?	--	Go to Step 13	--
12	Important: The new PCM must be programmed. Refer to Powertrain Control Module Replacement/Programming . Replace the PCM. Is the action complete?	--	Go to Step 13	--
13	Using the scan tool, clear the DTCs. Start the engine. Allow the engine to idle until the normal operating temperature is reached. Select the DTC and the Specific DTC functions. Enter the DTC number that was set. Operate the vehicle within the conditions for setting this DTC until the scan tool indicates the diagnostic Ran. Does the scan tool indicate the diagnostic Passed?	--	Go to Step 14	Go to Step 2
14	Does the Scan tool display any additional undiagnosed DTCs?	--	Go to the Applicable DTC Table	System OK