P0122
DTC P0122 THROTTLE/PEDAL POSITION SENSOR/SWITCH "A" CIRCUITComponent Location:
GENERAL DESCRIPTION
The Electronic Throttle Control (ETC) system is made of the components throttle body, Throttle Position Sensor (TPS)1 & 2 and Accelerator Position Sensor (APS) 1 & 2. TPS1 & 2 are sharing the same source voltage and ground. The throttle valve opening is control by throttle motor which is controlled by Engine Control Module (ECM). The opposite position indicator shows inverted signal characteristics. TPS1 output voltage increases smoothly in proportion with the throttle valve opening angle after starting. TPS2 output voltage decreases in inverse proportion with the throttle valve opening angle after starting. TPS provides feedback to the ECM to control the throttle motor in order to control the throttle valve opening angle properly in response to the driving condition.
DTC DESCRIPTION
ECM sets DTC P0122 if the ECM detects signal voltage lower than the possible range of a properly operating TPS1.
DTC Detecting Condition:
Schematic Diagram:
Signal Waveform And Data Part 1:
Signal Waveform And Data Part 2:
Signal Waveform And Data Part 3:
MONITOR DTC STATUS
1. Connect scan tool and select "Diagnostic Trouble Codes (DTCs)" mode.
2. Press F4 (DTAL) to select DTC information from the DTCs menu.
3. Confirm that "DTC Readiness Flag" indicates "Complete". If not, drive the vehicle within conditions noted in the freeze frame data or enable conditions.
4. Read "DTC Status" parameter.
5. Is parameter displayed "History (Not Present) fault"?
NOTE:
- History (Not Present) fault : DTC occurred but has been cleared.
- Present fault : DTC is occurring at present time.
YES - Fault is intermittent caused by poor contact in the sensor's and/or the ECM's connector or was repaired and ECM memory was not cleared. Thoroughly Check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure
NO - Go to next step as below
POWER CIRCUIT INSPECTION
NOTE: Check for open or short circuit in harness. Refer to "Signal Waveform & Data" in the 'General Information" procedure
1. Ignition "OFF".
2. Disconnect TPS1 connector.
3. Ignition "ON" & Engine "OFF".
4. Measure voltage between terminal 2 of the sensor harness connector and chassis ground.
Specification : Approx. 5 V
5. Is voltage within the specification?
YES - Go to "Signal Circuit inspection" procedure.
NO - Possibility of open or short to ground in 5 V reference circuit. Repair as necessary and go to "Verification of Vehicle Repair" procedure
SIGNAL CIRCUIT INSPECTION
NOTE: Check for open or short circuit in harness. Refer to "Signal Waveform & Data" in the "General Information" procedure
1. Measure voltage between terminal 4 of the sensor harness connector and chassis ground
Specification : Approx. 5 V
2. Is voltage within the specification?
YES - Go to "Component Inspection" procedure
NO - Check the short to ground in signal circuit.
Repair as necessary and go to "Verification of Vehicle Repair" procedure
TERMINAL AND CONNECTOR INSPECTION
1. Many malfunctions in the electrical system are caused by poor harness(es) and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly Check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?
YES - Repair as necessary and go to "Verification of Vehicle Repair" procedure
NO - Go to next step as below
COMPONENT INSPECTION
1. Reconnect the TPS1 connector.
2. After engine starting, connect Scantool and monitor the "TPS1" parameter on the Scantool data list.
Specification :
- Closed throttle status : Approx. 0.2 - 0.8 V, Wide open throttle : Approx. 4.2 - 4.8 V
- Signal increases with throttle opening angle
3. Is sensor data near the specified value?
YES - Check for poor connection between ECM and component: backed out terminal, improper mating, broken locks or poor terminal to wire connection. Repair as necessary and go to "Verification of Vehicle Repair" procedure
NO - Check TPS1 for contamination, deterioration, or damage. Substitute with a known-good TPS1 and Check for proper operation. If the problem is corrected, replace TPS1 and then go to "Verification of Vehicle Repair" procedure.
NOTE: It is necessary to perform the TPS adaptation procedure with Scan tool when the throttle body assembly or ECM is replaced.
- TPS adaptation procedure
1. Erase previous TPS adaptation value using Scan tool.
2. Ignition "OFF" and then "ON" without cranking. Wait for 10 seconds under enable conditions
- Enable conditions : Battery 10 V & Intake Air Temp. 5.3 °C(41.5 °F) & 5.3 °C (41.5 °F) Engine Coolant Temp. 99.8 °C (211.6 °F)
3. After TPS adaptation, the system normality should be confirmed by reading out "FMY" on the Scan Tool.
VERIFICATION OF VEHICLE REPAIR
After a repair, it is essential to verify that the fault has been corrected.
1. Connect scan tool and select "Diagnostic Trouble Codes (DTCs)" mode.
2. Press F4 (DTAL) and confirm that "DTC Readiness Flag" indicates "Complete". If not, drive the vehicle within conditions noted in the freeze frame data or enable conditions.
3. Read "DTC Status" parameter.
4. Is parameter displayed "History (Not Present) fault"?
YES - System performing to specification at this time. Clear the DTC.
NO - Go to the applicable troubleshooting procedure.