Diagnostic Test
- CHECK FOR AN ACTIVE DTC NOTE:
If P2101 is also set, make sure that the blade moves freely and does not hang up near Wide Open Throttle before trying to repair P0123.
- THROTTLE FOLLOWER TEST
- Turn the ignition on.
- With the scan tool, perform the ETC Throttle Follower Test and monitor the TPS 1 or TPS 2 voltage.
- Slowly press the accelerator pedal down.NOTE:
The voltage for TPS 1 should start at approximately 0.7 volts and increase to approximately 4.3 volts.
Is the TPS 1 voltage within the range of the listed specification?
Yes
- Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
No
- Go To 3
- CHECK THE (K22) TPS 1 SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE
- Turn the ignition off.
- Disconnect the Throttle Body harness connector.
- Turn the ignition on.
- Measure the voltage on the (K22) TPS 1 Signal circuit at the Throttle Body harness connector.
Is the voltage reading above 5.2 volts?
Yes
- Repair the (K22) TPS 1 Signal circuit for a short to voltage.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 4
- CHECK THE (K22) TPS 1 SIGNAL CIRCUIT FOR AN OPEN/HIGH RESISTANCE
- Turn the ignition off.
- Disconnect the PCM C2 harness connector.CAUTION:
Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install the GPEC Diagnostic Adaptor to perform the diagnosis.
- Connect the (special tool #10436, Adapter, GPEC Diagnostic).
- Measure the resistance of the (K22) TPS 1 Signal circuit from the Throttle Body harness connector to the GPEC Adaptor.
Is the resistance below 3.0 Ohms?
Yes
- Go To 5
No
- Repair the (K22) TPS 1 Signal circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
- CHECK FOR THE (K22) TPS 1 SIGNAL CIRCUIT SHORTED TO THE (F855) 5-VOLT SUPPLY CIRCUIT
- Check for continuity between the (K22) TPS 1 Signal circuit and the (F855) 5-Volt Supply circuit in the Throttle Body harness connector.
Is there continuity between the (K22) TPS 1 Signal circuit and the (F855) 5-Volt Supply circuit?
No
- Go To 6
Yes
- Repair the short between the (F855) 5-Volt Supply circuit and the (K22) TPS 1 Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
- Check for continuity between the (K22) TPS 1 Signal circuit and the (F855) 5-Volt Supply circuit in the Throttle Body harness connector.
- CHECK FOR THE (K22) TPS 1 SIGNAL CIRCUIT SHORTED TO THE (F855) 5-VOLT SUPPLY CIRCUIT
- Check for continuity between the (K22) TPS 1 Signal circuit and the (F855) 5-Volt Supply circuit in the Throttle Body harness connector.
Is there continuity between the (K22) TPS 1 Signal circuit and the (F855) 5-Volt Supply circuit?
No
- Go To 7
Yes
- Repair the short between the (F855) 5-Volt Supply circuit and the (K22) TPS 1 Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
- Check for continuity between the (K22) TPS 1 Signal circuit and the (F855) 5-Volt Supply circuit in the Throttle Body harness connector.
- CHECK THE (K22) TPS 1 SIGNAL CIRCUIT FOR A SHORT TO THE (K126) ETC MOTOR (-) CIRCUIT
- Check for continuity between the (K22) TPS 1 Signal circuit and the (K126) ETC Motor (-) circuit at the Throttle Body harness connector.
Is there continuity between the (K22) TPS 1 Signal circuit and the (K126) ETC Motor (-) circuit?
Yes
- Repair the short between the (K22) TPS 1 Signal circuit and the (K126) ETC Motor (-) circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 8
- Check for continuity between the (K22) TPS 1 Signal circuit and the (K126) ETC Motor (-) circuit at the Throttle Body harness connector.
- CHECK THE (K922) TPS RETURN CIRCUIT FOR AN OPEN/HIGH RESISTANCE
- Measure the resistance of the (K922) TPS Return circuit from the Throttle Body harness connector to the GPEC Adaptor.
Is the resistance below 3.0 Ohms?
Yes
- Go To 9
No
- Repair the (K922) TPS Return circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
- Measure the resistance of the (K922) TPS Return circuit from the Throttle Body harness connector to the GPEC Adaptor.
- THROTTLE POSITION SENSOR
- Turn the ignition off.
- Reconnect the PCM C2 harness connector.
- Turn the ignition on, engine not running.
- Connect a jumper between the (K22) TPS 1 Signal circuit and the (K922) TPS Return circuit at the Throttle Body harness connector.
- With the scan tool, read DTCs.NOTE:
The scan tool should display a P0122-THROTTLE POSITION SENSOR 1 CIRCUIT LOW DTC as active or pending with the jumper in place.
Does the scan tool display the DTC as described above?
Yes
- Verify that there is good pin to terminal contact in the Throttle Body and Powertrain Control Module connectors. If no problems are found, replace the Throttle Body Assembly. Refer to THROTTLE BODY, REMOVAL . Disconnect the Battery when replacing the Throttle Body Assembly. After installation is complete, using a scan tool select the ETC RELEARN function.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 10
- CHECK RELATED PCM AND COMPONENT CONNECTIONS
- Perform any Service Bulletins that apply.
- Disconnect all PCM harness connectors.
- Disconnect all related in-line harness connections (if equipped).
- Disconnect the related component harness connectors.
- Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
- Proper connector installation.
- Damaged connector locks.
- Corrosion.
- Other signs of water intrusion.
- Weather seal damage (if equipped).
- Bent terminals.
- Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
- Terminals that have been pushed back into the connector cavity.
- Check for spread terminals and verify proper terminal tension.
Repair any conditions that are found.
- Reconnect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
- Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
- Reconnect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
- With the scan tool, erase DTCs.
- Test drive or operate the vehicle in accordance with the when monitored and set conditions.
- With the scan tool, read DTCs.
Did the DTC return?
Yes
- Replace the Powertrain Control Module in accordance with the Service information. Refer to MODULE, POWERTRAIN CONTROL, REMOVAL .
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
- Test complete.