Q: How to check and troubleshoot wiper motor issues on 1996 through 2002 Toyota 4Runner?
A: Make sure your battery is working well and has charged up properly before you blame the wiper issue. First, check the battery power on the wipers. If the battery works well, take out the wiper motor, use your hands to move the wiper arms, and fix binding linkage and pivots while you're at it. Then put the motor back. If the wipers continue to move slowly after checking connections and the ground wire, take the motor out and replace it - only do this if all electrical connections seem good. When wipers do not work when switched on, inspect the fuse first; if normal, connect a connecting wire between wiper motor and ground, then recheck to see if it works. First fix the ground connection if the motor works; if not, disconnect the electrical connector from the motor and measure electrical current. If voltage is present, check the motor. On 4Runners, you need to take off the liftgate trim panel to get to the rear wiper motor's terminals. To test the wiper motor, use jumper wires to join one battery terminal lead to the engine body at pin 2, and the other lead from the other battery terminal to the motor chassis. Start by grounding the battery power leads. Next, hook up one positive lead to terminal number 1 and the other negative lead to the center of the motor. Check that the motor turns fast and loud. When you run the motor slowly, move the lead from terminal 2 to another connection point outside the motor's stopping point. Then, join terminals 2 and 3 together, attach one battery wire to terminal 4 and the other to the metal motor frame, and test whether the motor stops as soon as the stop position is reached. If the motor doesn't operate, replace it. To make sure the rear wiper works well, use two wires to connect one battery positive end to terminal 1 and the negative end to terminal 3. You'll see the wiper motor spinning in a clockwise direction. Switching battery connections checks this motor for the opposite direction. Attach the positive lead from the battery to terminal 3 and the negative link to terminal 1, then test the current flow using different motor connections shown on the linkage diagram. If the rear motor doesn't operate, replace it. To get to the front wiper motor, take off the cowl, disconnect its electrical connector, and remove three wiper mounting bolts. Pull out the motor, pry off its lever arm, and disconnect it from the wiper link. Separated bolts from cowl allow you to take out the wiper linkage by sliding it through a vent opening. Reassemble everything in the reverse order when installing it back. Using a wrench, unfasten the rear wiper's arm cover and nut, enter the car through the liftgate, pull off the trim panel and service hole cover, unscrew the bolts holding the motor, disconnect the electric connection, then elevate the wiper motor by hand. Installation goes in reverse order.