P1593

P1593-SPEED CONTROL SWITCH 1/2 STUCK

For a complete wiring diagram, refer to the Wiring Information.

Theory of Operation

The vehicle operator controls all speed control system features through the speed control switch pod on the face of the right horizontal spoke of the steering wheel. When a push button of the switch pod is depressed, it provides a hard wired resistor multiplexed analog input to the Body Control Module (BCM). The BCM is a gateway to the Controller Area Network (CAN) data bus and not only reads the hard wired speed control switch and stop (brake) lamp switch inputs, but also relays these inputs to the Powertrain Control Module (PCM) over the CAN bus.

- When Monitored:
Continuously with the ignition on.

- Set Conditions:
Fault signifies when the switch voltage does not register a valid cruise position.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.

Diagnostic Test
CHECK FOR AN ACTIVE DTC
1. Turn the ignition on.
2. With the scan tool, read DTCs.

NOTE: Diagnose andy CAN Bus DTCs in the PCM and BCM as well as and Speed Control DTCs in the BCM before continuing.

Does the scan tool display this DTC as active?

Yes

NOTE: Visually and physically inspect the wiring harness between the Speed Control Switch harness connector and the BCM harness connector. Repair any damaged wires, connectors, and open/spread terminals. If harness is OK, proceed with test.

- Replace the Speed Control Switch. Speed Control Switch - Removal.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Perform the INTERMITTENT CONDITION diagnostic procedure. Intermittent Condition Test.