Circuit Description
The cruise control set/coast switch is an input to the powertrain control module (PCM). This input allows the PCM to control and hold a requested speed. The cruise control set/coast switch sends a ignition positive voltage signal to the PCM when the momentary switch is applied. This DTC sets if the PCM senses a voltage on the set/coast switch signal circuit when the voltage is not expected.
Conditions for Running the DTC
The cruise control switch is ON.
Conditions for Setting the DTC
The PCM detects the set/coast switch is ON for longer than 90 seconds.
Action Taken When the DTC Sets
| • | The PCM stores the DTC information into memory when the diagnostic runs and fails. |
| • | The malfunction indicator lamp (MIL) will not illuminate. |
| • | The PCM records the operating conditions at the time the diagnostic fails. The PCM stores this information in the Failure Records. |
| • | The cruise is disabled. |
Conditions for Clearing the MIL/DTC
| • | A last test failed, or the current DTC, clears when the diagnostic runs and does not fail. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if failures are not reported by this or any other emission related diagnostic. |
| • | Use a scan tool in order to clear the MIL/DTC. |
Diagnostic Aids
Important: For any test that requires probing the PCM or a component harness connector, use the J 35616 Connector Test Adapter Kit. Using this kit prevents damage to the harness/component terminals. Refer to Using Connector Test Adapters in Wiring Systems.
| • | Inspect for a set/coast switch stuck in the engaged position or the signal circuit is shorted to voltage. |
| • | For an intermittent, refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. |
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Cruise Control Schematics | |||
1 | Did you perform A Diagnostic System Check - Cruise Control? | Go to Step 2 | |
Important: If DTC P1518 is also set, diagnose P1518 first. Does the scan tool parameter indicate that the cruise control set/coast switch is ON? | Go to Step 3 | Go to Diagnostic Aids | |
3 |
Does the scan tool indicate that the cruise control set/coast switch is ON? | Go to Step 4 | Go to Step 5 |
4 | Test the cruise control ON switch signal circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 9 | Go to Step 6 |
5 | Inspect for poor connections at the harness connector of the cruise control switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 9 | Go to Step 7 |
6 | Inspect for poor connections at the harness connector of the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 9 | Go to Step 8 |
7 | Replace the cruise control switch. Refer to Multifunction, Turn Signal, and Hazard Switch Replacement in Steering Wheel and Column. Did you complete the repair? | Go to Step 9 | -- |
8 |
Important: The PCM must be reprogrammed after replacement. Refer to Powertrain Control Module Programming in Engine Controls. Replace the PCM. Refer to Powertrain Control Module Replacement in Engine Controls. Did you complete the repair? | Go to Step 9 | -- |
9 |
Does the DTC reset? | Go to Step 2 | System OK |
