P2123, P2128 Accelerator Pedal Position Sensor 1, 2 Circuit High
October 28, 2018
Add Comment
P2123, P2128 code - The Powertrain Control Module (PCM) detects that the correlation between APP sensor 1 and APP sensor 2 is not plausible. Default actions the MIL light illuminate, the ETC light flash, the Throttle input and vehicle speed are limited.
- APP sensor signal 2 circuit shorted to battery voltage
- APP sensor signal 2 circuit shorted to an APP sensor 5 Volt supply circuit
- Accelerator Pedal position sensor
- Powertrain Control Module (PCM)
Diagnose and repar any system voltage or sensor supply voltage DTCs before continuing with this test. Turn the ignition on with the scan tool, read DTCs and record the repair order.
Is the DTC active or pending?
Yes, go to step 2.
No, perform the PCM intermittent condition.
Step 2. Check the 5 Volt supply circuit for a short to voltage
Turn the ignition off, disconnect the APP sensor harness connector. Turn the ignition on, measure the voltage on the 5 Volt supply circuit at the APP sensor harness connector.
Is the voltage above 5.2 volts?
Yes, repair the 5 Volt supply circuit for a short to voltage.
No, go to step 3.
Step 3. Check the APP sensor signal 1 circuit for a short to battery voltage
Measure the voltage on the APP sensor signal 1 circuit at the APP sensor harness connector.
Is the voltage above 5.2 volts?
Yes, repair the APP sensor signal 1 circuit for a short to battery voltage.
No, go to step 4.
Step 4. Check the APP sensor signal 1 circuit for a short to the 5 volt supply circuit
Turn the ignition off, disconnect the PCM harness connector. Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Check for continuity between the APP sensor signal 1 circuit and the 5 Volt supply circuit at the APP sensor harness connector.
Is there continuity between the APP sensor signal 1 circuit and the 5-Volt supply circuit?
Yes, repair the APP sensor signal 1 circuit for a short to the 5-Volt supply circuit.
No, go to step 5.
Step 5. Check the APP sensor signal 1 circuit for a short to the 5-volt supply circuit
Check for continuity between the APP sensor signal 1 circuit and the 5-volt supply circuit at the APP sensor harness connector.
Is there continuity between the APP sensor signal 1 and the 5-volt supply circuit?
Yes, repair the APP signal 1 circuit for a short to the 5-volt supply circuit.
No, go to step 6.
Step 6. Check the accelerator pedal position sensor
Reconnect the PCM harness connector, connect a jumper between the 5-volt supply circuit and the APP sensor ground circuit at the APP sensor harness connector. Turn the ignition on, with the scan tool read DTCs. The P2122 ACCELERATOR PEDAL POSITION SENSOR 1 CIRCUIT LOW DTC should display active or pending with the jumper in place.
Does the scan tool display as described above?
Yes, replace the accelerator pedal position sensor.
No, go to step 7.
Step 7. Check related PCM and component connections
Possible causes P2123, P2128 code
- 5 Volt supply circuit shorted to voltage- APP sensor signal 2 circuit shorted to battery voltage
- APP sensor signal 2 circuit shorted to an APP sensor 5 Volt supply circuit
- Accelerator Pedal position sensor
- Powertrain Control Module (PCM)
Diagnostic test 2123, P2128 code
Step 1. Check for an active DTCDiagnose and repar any system voltage or sensor supply voltage DTCs before continuing with this test. Turn the ignition on with the scan tool, read DTCs and record the repair order.
Is the DTC active or pending?
Yes, go to step 2.
No, perform the PCM intermittent condition.
Step 2. Check the 5 Volt supply circuit for a short to voltage
Turn the ignition off, disconnect the APP sensor harness connector. Turn the ignition on, measure the voltage on the 5 Volt supply circuit at the APP sensor harness connector.
Is the voltage above 5.2 volts?
Yes, repair the 5 Volt supply circuit for a short to voltage.
No, go to step 3.
Step 3. Check the APP sensor signal 1 circuit for a short to battery voltage
Measure the voltage on the APP sensor signal 1 circuit at the APP sensor harness connector.
Is the voltage above 5.2 volts?
Yes, repair the APP sensor signal 1 circuit for a short to battery voltage.
No, go to step 4.
Step 4. Check the APP sensor signal 1 circuit for a short to the 5 volt supply circuit
Turn the ignition off, disconnect the PCM harness connector. Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Check for continuity between the APP sensor signal 1 circuit and the 5 Volt supply circuit at the APP sensor harness connector.
Is there continuity between the APP sensor signal 1 circuit and the 5-Volt supply circuit?
Yes, repair the APP sensor signal 1 circuit for a short to the 5-Volt supply circuit.
No, go to step 5.
Step 5. Check the APP sensor signal 1 circuit for a short to the 5-volt supply circuit
Check for continuity between the APP sensor signal 1 circuit and the 5-volt supply circuit at the APP sensor harness connector.
Is there continuity between the APP sensor signal 1 and the 5-volt supply circuit?
Yes, repair the APP signal 1 circuit for a short to the 5-volt supply circuit.
No, go to step 6.
Step 6. Check the accelerator pedal position sensor
Reconnect the PCM harness connector, connect a jumper between the 5-volt supply circuit and the APP sensor ground circuit at the APP sensor harness connector. Turn the ignition on, with the scan tool read DTCs. The P2122 ACCELERATOR PEDAL POSITION SENSOR 1 CIRCUIT LOW DTC should display active or pending with the jumper in place.
Does the scan tool display as described above?
Yes, replace the accelerator pedal position sensor.
No, go to step 7.
Step 7. Check related PCM and component connections
0 Response to "P2123, P2128 Accelerator Pedal Position Sensor 1, 2 Circuit High"
Post a Comment