The throttle position (TP) sensors 1 and 2 are located within the throttle body assembly. The TP sensors share a common 5-volt reference circuit and a common low reference circuit. The 5-volt reference circuit is also shared with the accelerator pedal position (APP) sensor 2. The 5-volt reference voltage is supplied on 2 separate engine control module (ECM) terminals, but the terminals are connected internally to the same voltage supply. Each TP sensor has an individual signal circuit, which provides the ECM with a signal voltage proportional to throttle the plate movement. When the throttle plate is in the closed position, the TP sensor 1 signal voltage is near the low reference and increases as the throttle plate is opened. The TP sensor 2 signal voltage at closed throttle is near the 5-volt reference and decreases as the throttle plate is opened. If the ECM detects that the TP sensors are not within a predicted value from each other, DTC P2135 sets.
This diagnostic procedure supports the following DTC:
DTC P2135 Throttle Position (TP) Sensor 1-2 Correlation
| • | DTCs P0122, P0123, P0222, P0223, P0601, P0602, P0603, P0604, P0606, P0607, P0641, P0651 are not set. | 
| • | The ignition is ON. | 
| • | DTC P2135 runs continuously once the above condition is met. | 
The ECM detects that the difference between TP sensor 1 and TP sensor 2 is more than the predicted value for less than 1 second.
| • | The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails. | 
| • | The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame and/or the Failure Records. | 
| • | The control module commands the TAC system to operate in the Reduced Engine Power mode. | 
| • | A message center or an indicator displays Reduced Engine Power. | 
| • | Under certain conditions the control module commands the engine OFF. | 
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. | 
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. | 
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. | 
| • | Clear the MIL and the DTC with a scan tool. | 
Step  | Action  | Value(s)  | Yes  | No  | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Control Module Connector End Views or Engine Controls Connector End Views  | ||||||||||
1  | Did you perform the Diagnostic System Check - Vehicle?  | --  | Go to Step 2  | |||||||
2  | Observe the DTC information with a scan tool. Is DTC P0101, P0121, P0122, P0123, P0222, P0223, P2120, P2122, P2123, P2125, P2127, P2128 also set?  | --  | Go to Step 3  | |||||||
3  | 
 
 
 
 Is the resistance more than the specified value for any circuit?  | 5 ohms  | Go to Step 7  | Go to Step 4  | ||||||
4  | Test the signal circuit of the TP sensor 1 for a short to the signal circuit of TP sensor 2. Refer to Circuit Testing and Wiring Repairs. Did you find and correct the condition?  | --  | Go to Step 9  | Go to Step 5  | ||||||
5  | Test for an intermittent and for a poor connection at the TP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs. Did you find and correct the condition?  | --  | Go to Step 9  | Go to Step 6  | ||||||
6  | Test for an intermittent and for a poor connection at the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs. Did you find and correct the condition?  | --  | Go to Step 9  | Go to Step 8  | ||||||
7  | Repair the high resistance in the circuit that measured above the specified value. Refer to Wiring Repairs. Did you complete the repair?  | --  | Go to Step 9  | --  | ||||||
8  | Replace the throttle body assembly. Refer to Throttle Body Assembly Replacement . Did you complete the replacement?  | --  | Go to Step 9  | --  | ||||||
9  | 
 Did the DTC fail this ignition?  | --  | Go to Step 2  | Go to Step 10  | ||||||
10  | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?  | --  | System OK  | |||||||