Cruze

DTC P0122, P0123, P0222, P0223, or P2135

The throttle body assembly contains 2 throttle position sensors. The throttle position sensors are mounted to the throttle body assembly and are not serviceable. The throttle position sensors provide a signal voltage that changes relative to throttle blade angle. The engine control module (ECM) supplies the throttle position sensors with a common 5 V reference circuit, a common low reference circuit, and 2 independent signal circuits.

The throttle position sensors have opposite functionality. Throttle position sensor 1 signal voltage decreases and throttle position sensor 2 signal voltage increases as the accelerator pedal increases to wide open throttle (WOT).

P0122 00, P0123 00, P0222 00, P0223 00

P2135 00

P0122 00

The ECM detects that the throttle position sensor 1 voltage is less than 0.34 V for more than 0.4 s.

P0123 00

The ECM detects that the throttle position sensor 1 voltage is more than 4.62 V for more than 0.4 s.

P0222 00

The ECM detects that the throttle position sensor 2 voltage is less than 0.25 V for more than 0.4 s.

P0223 00

The ECM detects that the throttle position sensor 2 voltage is more than 4.66 V for more than 0.4 s.

P2135 00

The difference between the throttle position sensor 1 and throttle position sensor 2 exceeds a predetermined value for more than 2 s.

P0122 00, P0123 00, P0222 00, P0223 00, or P2135 00

DTC P0122 00, P0123 00, P0222 00, P0223 00, and P2135 00 are Type A DTCs.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Throttle Actuator Control (TAC) System Description

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

1. Ignition ON, observe the Throttle Position Sensor 1 parameter. The reading should be between 0.18-4.63 V and change with accelerator pedal input.
2. Ignition ON, observe the Throttle Position Sensor 2 parameter. The reading should be between 4.7-0.13 V and change with accelerator pedal input.
3. Observe the DTC Information with a scan tool. DTCs P0122 00, P0123 00, P0222 00, P0223 00, and P2135 00 should not set.
4. Observe both Throttle Position Sensor 1 and Throttle Position Sensor 2 percentage parameters while quickly pressing the accelerator pedal from a closed throttle to WOT. Both Throttle Position Sensor 1 and Throttle Position Sensor 2 percentage parameters should change.
5. Operate the vehicle within the conditions for running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.

Note: You must perform the circuit/system verification before proceeding with circuit/system testing.

1. Ignition OFF, disconnect the harness connector at the Q38 Throttle Body. Allow sufficient time for the K20 Engine Control Module to completely power down.
2. Ignition OFF, test for less than 5 Ω between the Q38 Throttle Body harness connector low reference circuit terminal E and ground.

⇒	If greater than 5 Ω, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.

3. Ignition ON, test for 4.8-5.2 V between the Q38 Throttle Body harness connector 5 V reference circuit terminal C and ground.

⇒	If less than the specified range, test the 5 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.

⇒	If greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module.

4. Test for less than 1 V between the Q38 Throttle Body harness connector throttle position sensor 1 signal circuit terminal D and ground.

⇒	If greater than specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module.

5. Test for 4.8-5.2 V between the Q38 Throttle Body harness connector throttle position sensor 2 signal circuit terminal F and ground.

⇒	If less than specified range, test the signal circuit for a short to ground, or an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.

⇒	If greater than specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module.

6. Install a 3 A fused jumper wire between Q38 Throttle Body harness connector throttle position sensor 1 signal circuit terminal D and the 5 V reference circuit terminal C. Verify the scan tool Throttle Position Sensor 1 voltage parameter is greater than 4.8 V.

⇒	If less than the specified range, test the signal circuit for a short to ground, or an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.

7. Install a 3 A fused jumper wire between Q38 Throttle Body harness connector throttle position sensor 2 signal circuit terminal F and the low reference circuit terminal E. Verify the scan tool Throttle Position Sensor 2 voltage parameter is less than 0.1 V.

⇒	If greater than the specified range, test the signal circuit for a short to voltage, or an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.

8. Ignition OFF, disconnect the ECM X1 harness connector at the K20 Engine Control Module.
9. Test for less than 5 Ω on all Q38 Throttle Body harness connector throttle position sensor circuits between the following terminals:

•	The 5 V reference circuit terminal C to the corresponding ECM terminal X1-03.

•	The throttle position sensor 2 signal circuit terminal F to the corresponding ECM terminal X1-39

•	The throttle position sensor 1 signal circuit terminal D to the corresponding ECM terminal X1-26

⇒	If greater than 5 Ω, repair the affected circuit.

10. Test for infinite resistance between Q38 Throttle Body throttle position sensor 1 signal circuit terminal D and throttle position sensor 2 signal circuit terminal F.

⇒	If less than infinite resistance, repair the short between Q38 Throttle Body throttle position sensor 1 signal circuit and throttle position sensor 2 signal circuit.

11. If all circuits test normal, replace the Q38 Throttle Body.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.