Circuit Description
The throttle actuator control (TAC) module is a communication link between the cruise switches and the PCM. The cruise Set/Coast switch is an input to the TAC module. This input is then communicated from the TAC module to the PCM across serial data, allowing the PCM to control and hold a requested speed. The Cruise Set/Coast switch sends an ignition voltage to the TAC module when the switch is closed (ON). If the PCM receives an input when the module does not expect it, this DTC sets.
Conditions for Running the DTC
The Cruise switch is ON.
Conditions for Setting the DTC
The Set/Coast switch is ON for more than 90 seconds.
Action Taken When the DTC Sets
The PCM stores conditions which were present when the DTC set as Failure Records only. This information will not be stored as Freeze Frame Records.
Conditions for Clearing the MIL/DTC
| • | The DTC becomes history when the conditions for setting the DTC are no longer present. |
| • | The history DTC clears after 40 malfunction free warm-up cycles. |
| • | The PCM receives a clear code command from the scan tool. |
Diagnostic Aids
Inspect for the following:
A set/coast switch stuck in the engage position or the signal circuit is shorted to voltage.
Many situations may lead to an intermittent condition. Perform each inspection or test as directed.
Important: : Remove any debris from the connector surfaces before servicing a component. Inspect the connector gaskets when diagnosing or replacing a component. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion.
| • | Loose terminal connection |
| - | Use a corresponding mating terminal to test for proper tension. Refer to Testing for Intermittent Conditions and Poor Connections , and to Connector Repairs in Wiring Systems for diagnosis and repair. |
| - | Inspect the harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and faulty terminal to wire connection. Refer to Testing for Intermittent Conditions and Poor Connections , and to Connector Repairs in Wiring Systems for diagnosis and repair. |
| • | Damaged harness--Inspect the wiring harness for damage. If the harness inspection does not reveal a problem, observe the display on the scan tool while moving connectors and wiring harnesses related to the sensor. A change in the scan tool display may indicate the location of the fault. Refer to Wiring Repairs in Wiring Systems for diagnosis and repair. |
| • | Inspect the powertrain control module (PCM) and the engine grounds for clean and secure connections. Refer to Wiring Repairs in Wiring Systems for diagnosis and repair. |
If the condition is determined to be intermittent, reviewing the Snapshot or Freeze Frame/Failure Records may be useful in determining when the DTC or condition was identified.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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This step determines if the Resume/Accel signal circuit is shorted to voltage.
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This step determines if the TAC module or the switch is at fault.
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Inspect for a resume/accel switch stuck in the engaged position or for the signal circuit shorted to voltage.
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This DTC will not report a pass. The scan tool status for this DTC will never report a pass. The scan tool will only indicate the DTC when the diagnostic fails. The repair is not complete if the scan tool indicates that the diagnostic ran and failed.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | ||
Does the scan tool indicate the Cruise Set/Coast switch ON? | -- | Go to Diagnostic Aids | ||
Does the test lamp illuminate? | -- | |||
Repair the short to voltage on the Set/Coast switch signal circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | |||
5 | Replace the TAC module. Refer to Accelerator Pedal Replacement . Did you complete the replacement? | -- | -- | |
6 | Replace the multifunction lever. Refer to Multifunction Turn Signal Lever Replacement - On Vehicle in Steering Column. Did you complete the repair? | -- | -- | |
Does the DTC reset? | -- | |||
8 | Does the scan tool indicated any DTCs set that you have not diagnosed? | -- | Go to applicable DTC | System OK |
