S15/T15 4WD P/U V6-262 4.3L (1988)
Wiper Switch: Testing and Inspection
Fig. 3 Permanent Magnet Type Windshield Wiper Motor W/Pulse Wipers
1.
Disconnect electrical connectors from wiper motor.
2.
Check switch voltage using a digital voltmeter with ignition switch in the On position. If readings are not as specified at between various switch
positions and ground, replace switch.