For 1990-2009 cars

### Circuit Description

The ECM controls the throttle blade by applying varying voltage to the throttle valve motor. The ECM monitors the pulse width modulation that is required to move the throttle blade. If an incorrect amount of pulse width modulation is required to operate the throttle valve motor a DTC will set.

### Conditions for Running the DTC

• | The battery voltage must be greater than 7 volts.

• | The DTC learn procedure must not be active.

### Conditions for Setting the DTC

The pulse width modulation (PWM) is greater than 80 percent for longer than 6 seconds.

### Action Taken When the DTC Sets

The ECM illuminates the malfunction indicator lamp (MIL) and records the operating conditions in the Freeze Frame on the first drive trip that the diagnostic runs and fails. The vehicle will default to the limp home mode.

### Conditions for Clearing the MIL/DTC

• | The ECM turns off the MIL after 3 consecutive drive trips that the diagnostic runs and does not fail.

• | A History DTC clears after 40 consecutive warm up cycles in which no failures are reported by this diagnostic or any other emission related diagnostic.

• | The ECM battery voltage is interrupted.

• | The scan tool clears the MIL/DTC.

### Diagnostic Aids

Notice: Using the J 35616-A Connector Test Adapter Kit will prevent damage to the harness connector terminals.

Use the J 35616 connector test adapter kit for any test that requires probing the ECM harness connector or a component harness connector.

Check for the following conditions:

• | Poor connections at the ECM or at the component--Inspect the harness connectors for a poor terminal to wire connection. Refer to Engine Control Module Diagnosis , Checking Terminal Contact, for the proper procedure.

• | Damaged harness--Inspect the wiring harness for damage. If the harness appears to be OK, observe the scan tool while moving the related connectors and the wiring harnesses. A change in the display may help locate the fault.

Refer to Symptoms for the Intermittents.

Step | Action | Values | Yes | No
--- | --- | --- | --- | ---
1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | Go to Step 2 | Go to Powertrain On Board Diagnostic (OBD) System Check
2 |

1. Turn the ignition OFF.
2. Disconnect the TP sensor connector.
3. Connect the J 35616-200 unpowered test lamp between the throttle valve motor + and - circuit terminals.
4. Observe the test lamp as you turn the ignition ON leaving the engine OFF.

Did the test lamp flash ON and then go OFF?

--

Go to Step 4

Go to Step 3

3 |

1. Turn the ignition OFF.
2. Disconnect the ECM.
3. Test the Throttle Valve Motor circuits for the following:

• | opens

• | high resistance

• | shorts to ground

• | shorts to other circuits

• | Poor terminal contact at the ECM connector

4. Repair the wiring as necessary.

Was a problem found and repaired?

--

Go to Step 6

Go to Step 5

4 | Replace the throttle body assembly. Is the action complete? | -- | Go to Step 6 | --
5 | Important: This vehicle is equipped with a theft deterrent system that interfaces with the engine control module (ECM). Program the new ECM with the frequency code of the theft deterrent module that is currently in the vehicle. Replace the ECM. Refer to Engine Control Module Replacement/Programming .

Is the action complete?

--

Go to Step 6

--

6 |

1. Use a scan tool in order to clear the DTCs.
2. Start the engine.
3. Allow the engine to idle until the engine reaches the normal operating temperature.
4. Select the DTC and the Specific DTC function.
5. Enter the DTC number that was set.
6. Operate the engine within the Conditions for Running this DTC until the scan tool indicates the diagnostic Ran.

Does the scan tool indicate the diagnostic Passed?

--

Go to Step 7

Go to Step 2

7 | Does the scan tool display any additional undiagnosed DTCs? | -- | Go to the applicable DTC table | System OK