Wiper Switch: Description and Operation

SYSTEM OPERATION

Front

Multi-Function Switch:

The windshield wiper and washer switches are contained in the multi-function switch assembly. The multi-function switch assembly is secured to the left side of the steering column. A knob on the end of the multi-function switch stalk is rotated to select the desired wiper speed or intermittent wipe delay, or depressed toward the steering column to activate the washer system.

The multi-function switch contains circuitry for the following functions:
- Turn signals
- Hazard warning
- Headlamp beam selection
- Headlamp optical horn
- Windshield wipers
- Windshield washers.

The information addresses only the switch functions for the windshield wiper and washer systems. However, the multi-function switch cannot be repaired. If any function of the multi-function switch is faulty, or if the switch is damaged, the entire switch assembly must be replaced.

Rear
The single two-function rear wiper and washer switch is integral to the rear window switch pod, which includes the rear window defogger switch. The rear window switch pod is installed in the instrument panel lower bezel, which is located near the center of the lower instrument panel, below the heater and air conditioner controls. The rear wiper and washer switch controls the rear wiper and washer functions.

The rear window switch pod also contains the rear window defogger logic and timer circuitry, an amber defogger indicator lamp, the rear window defogger relay, and two switch illumination lamps. The indicator and illumination lamps in the switch pod use incandescent bulbs, which can be serviced.

The sliding-type switch features a detent in the On position for the rear wiper. Pushing in on the rear wiper switch button activates the momentary rear washer switch. The rear wiper and washer switch also has an integral illumination lamp with a serviceable bulb. Both the rear wiper and rear washer motors will operate continuously for as long as the switch is held in the momentary Wash position.

The rear wiper and washer switch cannot be repaired and, if faulty or damaged, the entire rear window switch pod must be replaced.

Central Timer Module
Two versions of the Central Timer Module (CTM) are available on this vehicle, a base version and a high-line version. The base version of the CTM is used on base models of the vehicle. The base version of the CTM combines the functions of a chime/buzzer module, an intermittent wipe module and an illuminated entry module into a single unit.

The high-line version of the CTM is used on high-line vehicles. The high-line CTM provides all of the functions of the base version CTM, but also is used to control and integrate many of the additional electronic functions and features included on the high-line models. The high-line version of the CTM contains a central processing unit and interfaces with other modules in the vehicle on the Chrysler Collision Detection (CCD) data bus network.

The CCD data bus network allows the sharing of sensor information. This helps to reduce wire harness complexity, reduce internal controller hardware, and reduce component sensor current loads. At the same time, this system provides increased reliability, enhanced diagnostics, and allows the addition of many new feature capabilities.

Both the base and the high-line versions of the CTM support the intermittent wipe and wipe-after- wash features, but only the high-line CTM supports the speed sensitive intermittent wipe. The intermittent wipe relay is one of the outputs that both the base and the high-line versions of the CTM can control. Each CTM is programmed to energize or de-energize the intermittent wipe relay in response to certain inputs from the windshield wiper and washer switches and from the windshield wiper motor park switch.

For the speed sensitive intermittent wipe feature, the high-line CTM also uses vehicle speed messages, which are received on the CCD data bus from the Powertrain Control Module (PCM).

Both versions of the CTM are mounted under the passenger side end of the instrument panel, outboard of the instrument panel glove box opening. Refer to Central Timer Module/Service and Repair of Instrument Panel Systems for the service procedures.

See Wiper System Testing and Inspection for diagnosis of the base version of the CTM. For diagnosis of the high-line version of the CTM or the CCD data bus, a DRB scan tool and the proper Diagnostic Procedures are recommended. The CTM cannot be repaired and, if faulty or damaged, it must be replaced.