Wipers and Washers - Front

FRONT

WARNING: To avoid serious or fatal injury on vehicles equipped with airbags, disable the Supplemental Restraint System (SRS) before attempting any steering wheel, steering column, airbag, seat belt tensioner, impact sensor, or instrument panel component diagnosis or service. Disconnect and isolate the battery negative (ground) cable, then wait two minutes for the system capacitor to discharge before performing further diagnosis or service. This is the only sure way to disable the SRS. Failure to take the proper precautions could result in accidental airbag deployment.

If the front wiper motor operates, but the wipers do not move on the windshield, replace the ineffective front wiper motor or module. If the washer pump/motor operates, but no washer fluid is dispensed on the glass; or, if the wipers operate, but chatter, lift, or do not clear the glass, clean and inspect the front wiper and washer system components as required. Wipers and Washers - Cleaning and Wipers and Washers - Inspection.

The hard wired front wiper and washer system circuits and components may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. The wiring information includes wiring diagrams, proper wire and connector repair procedures, details of wire harness routing and retention, connector pin-out information and location views for the various wire harness connectors, splices and grounds.

However, conventional diagnostic methods will not prove conclusive in the diagnosis of the front wiper and washer system or the electronic controls or communication between other modules and devices that provide some features of the front wiper and washer system. The most reliable, efficient, and accurate means to diagnose the front wiper and washer system or the electronic controls and communication related to front wiper and washer system operation requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.

FALSE WIPES (AUTOMATIC WIPER ONLY)

False wipes are unnecessary wipes that occur when the control knob of the right multi-function switch is in one of the five automatic wiper sensitivity positions and no rain or moisture is apparent within the wipe pattern on the windshield glass. Because this system is designed to operate whenever it detects moisture, if the switch is in one of the automatic wiper sensitivity positions any road spray, bug splatters, or mist from passing cars or trucks may occasionally cause the wipers to cycle. These are normal characteristics of this system and are not false wipes.

False wipes generally are the result of foreign material or flaws that interfere with the system optics. The optics for this system allow the Rain Sensor Module (RSM) (also known as the Rain Light Sensor Module/RLSM) to precisely transmit several InfraRed (IR) light beams and precisely monitor the intensity of these beams on the outer surface of the windshield glass to determine the presence of moisture. The sensitivity of this system is such that anything that distorts the focus or intensity of the IR light beams or affects the ability of the photo diodes within the RSM to see and accurately measure these light beams can result in the RSM logic misinterpreting the resulting input data as moisture on the windshield. The optics for this system include the lenses of the RSM, the lenses of the RSM bracket, the adhesive pad layer that bonds the RSM bracket to the inside of the windshield, and the windshield glass.

The following procedure should only be used if false wipe occurrences are frequent and persistent. Perform diagnosis of the front wiper system, the right multi-function switch, the Steering Control Module (SCM) and the RSM using a diagnostic scan tool and the appropriate diagnostic procedures before performing the following:

NOTE: The Rain Sensor Module (RSM) mounting bracket is serviced as a unit with the windshield glass. If either the bracket or the glass is ineffective or damaged, the entire RSM bracket and windshield glass unit must be replaced.

1. Carefully inspect the outer surface of the windshield glass for physical damage, including scratches, cracks or chips in the vicinity of the RSM mounting bracket lenses. Scratches, cracks or chips in the windshield glass outside the area of the RSM mounting bracket lenses will not cause false wipes. If OK, go to 2. If not OK, replace the damaged windshield.
2. From the outside of the windshield glass, carefully inspect the adhesive layer between the windshield glass and the RSM bracket for any large voids. If an adhesive void greater than about 1 millimeter (0.04 inch) is observed, replace the flawed RSM mounting bracket and windshield unit. If OK, go to 3.
3. Lightly pull the RSM away from the windshield bracket to confirm that both module sliding cam locks are fully engaged with all four pins of the mounting bracket on the inside of the windshield glass. If OK, go to 4. If not OK, reinstall the module onto the bracket as required.
4. Remove the RSM from the mounting bracket. Inspect the RSM lenses and the mounting bracket lenses for contamination. If OK, go to 5. If not OK, clean any foreign material from each of these lenses using rubbing alcohol and a lint-free cloth.
5. Carefully inspect the RSM for any physical damage, including scratches on the RSM lenses. If OK, go to 6. If not OK, replace the damaged RSM.
6. Carefully inspect the RSM mounting bracket for any physical damage, including scratches on the RSM bracket lenses. If not OK, replace the damaged RSM bracket and windshield as a unit.