Windshield Wipers TSB 99-24-3

99-24-3, Publication Date: NOVEMBER 12, 1999

FORD:

1999 TAURUS

1999-2000 MUSTANG

1999-2000 EXPEDITION, EXPLORER, F-150, F-250, RANGER, WINDSTAR

2000 EXCURSION

LINCOLN:

1999-2000 NAVIGATOR

MERCURY:

1999 SABLE

1999-2000 MOUNTAINEER, VILLAGER

This TSB is being republished in its entirety to correct the reference to the "Other Applicable Articles" listed in this TSB.

Explorer/Mountaineer built through 9/13/1999

Ranger built through 9/15/1999

Excursion built through 8/25/1999

Expedition/Navigator, F-150/250, Mustang, Windstar, Taurus/Sable, and Villager built through 8/16/1999

ISSUE:

The front windshield wipers may operate while the multifunction switch is in the OFF position on some vehicles. This may be caused by a resistance drift in the multifunction switch or a partially plugged-in connector.

ACTION:

Perform diagnostics per the appropriate Workshop Manual and if the uncommanded wiper operation condition still exists, replace the multifunction switch with a revised multifunction switch; for Explorer/Mountaineer and Ranger, replace both the multifunction switch and Generic Electronic Module (GEM). Refer to the following Service Procedure for details.

SERVICE PROCEDURE

NOTE:

MAKE SURE THAT ALL CONNECTIONS ARE FULLY SEATED TO THE GEM, CENTER INSTRUMENT PANEL COMPONENTS, FRONT WIPER MOTOR, AND MULTIFUNCTION SWITCH DURING INSTALLATION. CHECK THE MULTIFUNCTION SWITCH CONNECTION CLOSELY FOR LOOSE CONNECTIONS, TERMINALS, AND TERMINAL PUSH OUTS. DO NOT ATTEMPT A CONTINUITY CHECK OR PROBE THE CIRCUITS OF THE WIRE HARNESS.

Expedition/Navigator, F-150/250, Excursion, Villager, Mustang, Windstar, Taurus/Sable, and Ranger/Explorer with CTM

Perform diagnostics on the wiper system per the Workshop Manual. If the uncommanded wiper operation condition is present and no other symptoms apply to the vehicle being serviced, install a revised multifunction switch. DO NOT ATTEMPT TO REPAIR THE VEHICLE BY REPLACING THE GEM OR THE WIPER CONTROL MODULE. Refer to the Multifunction Switch Application Chart for the applicable switch.

Using Worldwide Diagnostic System (WDS), New Generation Star (NGS) Tester or Service Bay Diagnostic System (SBDS) on Expedition/Navigator, F-150/250, Excursion, Mustang, and Taurus/Sable, run GEM. Retrieve and Clear Continuous Diagnostic Trouble Codes (DTCs) and run On Demand Self-Test to make sure that no valid DTCs are set.

NOTE:

Explorer/Mountaineer, Ranger with GEM

Perform diagnostics on the wiper system per the Workshop Manual. If the uncommanded wiper operation condition is present and no other symptoms apply to the vehicle being serviced, install a revised multifunction switch and GEM. Refer to the Multifunction Switch Application Chart for Multifunction Switch and GEM part numbers (refer to TSB «99-18-13» to reconfigure GEM (Ranger with 2WABS) for speedometer operation).

Using NGS or SBDS, run GEM Retrieve and Clear Continuous Diagnostic Trouble Codes (DTCs) and run On Demand Self-Test to make sure that no valid DTCs are set. On Rangers with 2-Wheel ABS, make sure to program the tire size and axle ratio into the GEM after replacement, otherwise the speed indication will be in error. Refer to TSB «99-18-13».