Pinpoint Test B: The Wipers Stay On Continuously

WARNING: This page is about a different car, the 2010 Lincoln Town Car. However, it is still accessible from the selected car via links, so may be relevant.

Refer to appropriate SYSTEM WIRING DIAGRAMS article, Front Wipers and Washers for schematic and connector information.

Normal Operation

The windshield wiper motor receives open and ground inputs from the multi-function switch through circuits 56 (DB/OG), 58 (WH), 61 (YE/RD) and 63 (RD). When a wiper function is selected, the multi-function switch grounds 1 of several combinations of these 4 circuits. The windshield wiper motor interprets these ground signals and performs the action requested. The multi-function switch is grounded through circuit 57 (BK).

This pinpoint test is intended to diagnose the following:

Wiring, terminals or connectors
Multi-function switch
Windshield wiper motor

PINPOINT TEST B: THE WIPERS STAY ON CONTINUOUSLY

CAUTION: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

B1 CHECK THE MULTI-FUNCTION SWITCH
- Key in OFF position.
- Disconnect: Multi-function Switch C202b
- Preform the Multi-function Switch Component Test.
- Does the multi-function switch pass the component test?
1. YES : Go to B2.
2. NO : INSTALL a new multi-function switch. REFER to STEERING COLUMN SWITCHES article.

B2 CHECK CIRCUITS 56 (DB/OG), 58 (WH), 61 (YE/RD) AND 63 (RD) FOR A SHORT TO GROUND

Disconnect: Windshield Wiper Motor C125

Fig 1: Checking Circuit For Short To Ground

Courtesy of FORD MOTOR CO.

Using the following table, measure the resistance between windshield wiper motor C125 harness side and ground:

Windshield Wiper Motor C125	Circuit
Pin 10	Circuit 56 (DB/OG)
Pin 11	Circuit 58 (WH)
Pin 1	Circuit 61 (YE/RD)
Pin 9	Circuit 63 (RD)

Are the resistances greater than 10,000 ohms?

YES : Go to B3.
NO : REPAIR the circuit. TEST the system for normal operation.

B3 CHECK FOR CORRECT WIPER MOTOR OPERATION
- Disconnect all wiper motor connectors.
- Check for:
  - corrosion.
  - pushed-out pins.
- Connect all wiper motor connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
1. YES : INSTALL a new windshield wiper motor. REFER to Wiper Motor .
2. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. TEST the system for normal operation.