Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptors
DTC P0122: Throttle Position (TP) Sensor 1 Circuit Low VoltageDTC P0123: Throttle Position (TP) Sensor 1 Circuit High Voltage
DTC P0222: Throttle Position (TP) Sensor 2 Circuit Low Voltage
DTC P0223: Throttle Position (TP) Sensor 2 Circuit High Voltage
DTC P2135: Throttle Position (TP) Sensor 1-2 Correlation
Diagnostic Fault Information
Circuit | Short to Ground | High Resistance | Open | Short to Voltage | Signal Performance |
|---|---|---|---|---|---|
5-Volt Reference | P0122, P0222, P0641, P2106, P2110 | -- | P0122, P0222, P2106, P2110, P2135 | P0223, P0641, P2106, P2110, P2135 | -- |
TP Sensor 1 Signal | P0122, P2135 | P2135 | P0123, P2135 | P0123, P2135 | P2135 |
TP Sensor 2 Signal | P0222, P2135 | P2135 | P0222, P2135 | P0223, P2135 | P2135 |
Low Reference | -- | -- | P0123, P2106, P2110 | -- | -- |
Typical Scan Tool Data
Circuit | Short to Ground | Open | Short to Voltage |
|---|---|---|---|
Operating Conditions: The ignition is ON and the engine is OFF. Parameter Normal Range: TP Sensor 1 7-21% | |||
5-Volt Reference | 0% | 0% | 30-40% |
TP Sensor 1 Signal | 0% | 80-90% | 85-99% |
Low Reference | -- | 85-95% | -- |
Circuit | Short to Ground | Open | Short to Voltage |
|---|---|---|---|
Operating Conditions: The ignition is ON and the engine is OFF. Parameter Normal Range: TP Sensor 2 7-21% | |||
5-Volt Reference | 80-90% | 80-90% | 0% |
TP Sensor 2 Signal | 80-90% | 80-90% | 0% |
Low Reference | -- | 0% | -- |
Circuit/System Description
The throttle body assembly contains 2 throttle position (TP) sensors. The TP sensors are mounted to the throttle body assembly and are not serviceable. The TP sensors provide a signal voltage that changes relative to throttle blade angle. The engine control module (ECM) supplies the TP sensors with a common 5-volt reference circuit, a common low reference circuit, and 2 independent signal circuits.
The TP sensors have opposite functionality . TP sensor 1 signal voltage increases from below 1 volt at idle to above 4 volts at wide open throttle (WOT). TP sensor 2 signal voltage decreases from above 4 volts at idle to below 1 volt at WOT.
Conditions for Running the DTC
| • | The ignition is ON or the engine is running. |
| • | The DTCs runs continuously when the above condition is met. |
Conditions for Setting the DTC
P0122
The ECM detects that the TP sensor 1 voltage is less than 0.3 volt for less than 1 second.
P0123
The ECM detects that the TP sensor 1 voltage is greater than 4.8 volts for less than 1 second.
P0222
The ECM detects that the TP sensor 2 voltage is less than 0.3 volt for less than 1 second.
P0223
The ECM detects that the TP sensor 2 voltage is greater than 4.8 volts for less than 1 second.
P2135
The ECM detects that TP sensor 1 and TP sensor 2 disagree greater than 4.5 percent for less than 1 second.
Action Taken When the DTC Sets
P0122 or P0123
| • | DTC P0122 and P0123 are type B DTCs |
| • | The ECM uses TP sensor 2 for throttle control. |
P0222 or P0223
| • | DTC P0222 and P0223 are type B DTCs |
| • | The ECM uses TP sensor 1 for throttle control. |
P2135
| • | DTC P2135 is a type B DTC. |
| • | The ECM commands the throttle actuator control (TAC) system to operate in a Reduced Engine Power mode. |
| • | The ECM commands the reduced engine power indicator ON. |
Conditions for Clearing the DTC
DTCs P0122, P0123, P0222, P0223, and P2135 are type B DTCs.
Diagnostic Aids
| • | If a shared 5-volt reference circuit is shorted to ground or shorted to a voltage, other 5-volt reference circuits may be affected. |
| • | The scan tool 5 volt reference parameter should display between 4.8-5.2 volts. |
Reference Information
Schematic Reference
Connector End View Reference
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
Circuit/System Verification
- Ignition ON, observe the DTC information with a scan tool. Verify DTC P0641 is not set.
- Ignition ON, observe the TP Sensor percentage parameters with a scan tool. Verify the scan tool TP sensors parameters are between 7-21 percent.
- Observe both TP Sensor percentage parameters while pressing the accelerator pedal from a closed throttle to WOT. Both TP Sensor percentage parameters should change.
- Rapidly depress the accelerator pedal from the rest position to the WOT position and release pedal. Repeat the procedure several times. DTCs P0122, P0123, P0222, P0223, or P2135 should not set.
- Slowly depress the accelerator pedal to WOT and then slowly return the pedal to closed throttle. Repeat the procedure several times. DTCs P0122, P0123, P0222, P0223, or P2135 should not set.
- 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.
| ⇒ | If P0641 is set, refer to DTC P0641 or P0651 . |
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the throttle body assembly.
- Ignition OFF, test for 5 ohms or less of resistance between the low reference circuit terminal 1 and ground.
- Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal 5 and ground.
- Verify both scan tool TP sensor percentage parameters are between 80-88 percent.
- Install a 3A fused jumper wire between TP sensor 1 signal circuit terminal 6 and ground. Verify the scan tool TP sensor 1 percentage parameter is less than 2 percent.
- Install a 3A fused jumper wire between TP sensor 2 signal circuit terminal 4 and the 5-volt reference circuit terminal 5. Verify the scan tool TP sensor 2 percentage parameter is less than 2 percent.
- If all circuits test normal, test or replace the throttle body assembly.
| ⇒ | If greater than the specified range, test the low reference circuit for a short to voltage, or an open/high resistance. If the circuit tests normal, replace the ECM. |
| ⇒ | If less than the specified range, test the 5-volt reference circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the ECM. |
| ⇒ | If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM. |
| • | If TP sensor 1 is less than the specified range, test the signal circuit for a short to ground. If the circuit tests normal, replace the ECM. |
| • | If TP sensor 1 is greater than specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the ECM. |
| • | If TP sensor 2 is less than specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the ECM. |
| • | If TP sensor 2 is greater than specified range, test the signal circuit for a short to ground. If the circuit tests normal, replace the ECM. |
| ⇒ | If greater than the specified range, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the ECM. |
| ⇒ | If greater than the specified range, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the ECM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for ECM replacement, setup, and programming |
