2012 Jeep Wrangler JK Factory Service Manual 28 - DTC-Based Diagnostics

P0579-SPEED CONTROL SWITCH 1 PERFORMANCE

P0579-SPEED CONTROL SWITCH 1 PERFORMANCE

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





Theory of Operation

The Speed Control Switches are located in the Right Steering Wheel Switch. The Right Steering Wheel Switch is hardwired to the Powertrain Control Module (PCM) via the clockspring pass-through within the Steering Column Control Module (SCCM). The SCCM is located near the top of the steering column below the steering wheel. The SCCM includes the steering column shroud, the Steering Angle Sensor (SAS), the Clockspring, the Multi-function Switch, a Steering Column Power Tilt and Telescope Switch (if equipped), and a trim cover.


Possible Causes

S/C SIGNAL 1 AND S/C SWITCH GROUND CIRCUITS
SPEED CONTROL SWITCH (RIGHT STEERING WHEEL SWITCH)
CLOCKSPRING

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).


1. CHECK FOR AN ACTIVE DTC


WARNING:

Turn the ignition off disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.

WARNING:

Do not place an intact non-deployed airbag face down on a hard surface, the airbag propels into the air if accidentally deployed. Failure to follow these instructions may result in possible serious or fatal injury.

1. Turn the ignition on.
2. With the scan tool, read DTCs


Does the scan tool display this DTC as active?

Yes


No


2. (V937) S/C SWITCH GROUND CIRCUIT


1. Turn the ignition off.
2. Disconnect the Steering Wheel Jumper harness connector from the Right Steering Wheel Switch.
3. Ignition on, engine not running.
4. Measure the voltage between the (V937) S/C Switch Ground circuit and the (V71/V37) S/C Signal 1 circuit in the Steering Wheel Jumper harness connector.


Is the voltage between 4.5 and 5.2 Volts DC?

Yes


No