Circuit/System Testing

Clear DTCs with the scan tool. Operate the vehicle within the Conditions for Running the DTC or within the conditions that you observed from the Freeze Frame/Failure Records.
Ignition ON, use a scan tool to observe the TP sensor 1 voltage with the accelerator pedal in the rest position. Voltage should be between 0.27-4.67 volts.
- If more than 4.67 volts, test the low reference for an open or a faulty PCM.
- If less than 0.27 volt, test the TP sensor 1 signal circuit for a short to ground or a faulty PCM.
With the ignition ON, observe the TP sensor 2 voltage with the accelerator pedal in the rest position with a scan tool. Voltage should be between 0.31-4.7 volts.
- If more than 4.7 volts, test the low reference for an open or a faulty PCM.
- If less than 0.31 volt, test the TP sensor 2 signal circuit for a short to ground or a faulty PCM.
Ignition ON, use a scan tool to observe the DTCs
- If DTC P0120 is the only code set, replace the PCM.
- If DTC P0220 is the only code set, replace the PCM.
- If any other codes are set refer to that code first Diagnostic Trouble Code (DTC) List - Vehicle .
Disconnect the throttle body harness connector and verify the scan tool TP sensor 1 voltage is less than 0.1 volts.
- If more than 0 volt, test the TP sensor 1 signal circuit for a short to voltage or a faulty PCM.
With the throttle body harness connector still disconnected, verify the scan tool TP sensor 2 voltage is more than 4.8 volts.
- If less than 4.8 volts, test the TP sensor 2 signal circuit for a short to ground or a faulty PCM.
Ignition ON, test for 4.8-5.2 volts between both 5-volt reference circuits and the negative terminal of the battery.
- If more than 5.2 volts, test both 5-volt reference circuits for a short to voltage or faulty PCM.
- If less than 4.8 volts, test both the 5-volt reference circuits for an open or short to ground or a faulty PCM.
Install a 3-amp fused jumper wire between the signal circuit and the 5-volt reference circuit of the TP sensor 1 and verify the TP sensor 1 voltage is more than 4.8 volts.
- If less than 4.8 volts, test the TP sensor 1 signal circuit for an open or a
Install a test lamp between the signal circuit and the negative terminal of the battery of the TP sensor 2 and verify the TP sensor 2 voltage is less than 0.1 volt.
- If more than 0.1 volt, test the TP sensor 2 signal circuit for an open or a faulty PCM.
- If test lamp illuminates, test the TP sensor 2 signal circuit for a short to voltage or faulty PCM.
If all circuits test normal, replace the throttle body.