16. Figure 44–5a A circuit diagram is necessary to troubleshoot a windshield wiper problem.
17. Figure 44–5b A circuit diagram is necessary to troubleshoot a windshield wiper problem. See complete schematic on Page 497 of your textbook.
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20. Figure 44–7 (a) A typical wiper motor with the housing cover removed. The motor itself has a worm gear on the shaft that turns the small intermediate gear, which then rotates the gear and tube assembly, which rotates the crank arm (not shown) that connects to the wiper linkage. (b) If the brush retainer becomes loose, the wiper motor will stop because the brushes get their ground connection through the retainer and housing. Continued
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22. Figure 44–8 A typical wiring diagram of a two-speed windshield wiper circuit using a three brush, two-speed motor. The dashed line for the multifunction lever indicates that the circuit shown is only a part of the total function of the steering column lever. Continued
23. Figure 44–9 A typical wiring diagram of a three-speed windshield wiper circuit using a two-brush motor, but both a series and a shunt field coil. Continued
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25. Figure 44–10 A variable pulse rate windshield wiper circuit. Notice that the wiring travels from the passenger compartment to underhood through rubber grommets called pass-throughs. Continued
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36. Figure 44–15 Circuit diagram of a rheostat-controlled, electronically timed interval wiper. Continued
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39. Figure 44–16 Disconnect the hose at the pump and operate the switch to check a washer pump. To quick-check any washer system, make sure the reservoir has fluid, disconnect the hose and operate the washer switch. If fluid squirts from the pump, the delivery system is at fault, not the motor, switch, or circuitry. If no fluid squirts from the pump, it may be circuit failure, defective pump, or faulty switch A clogged reservoir screen may be preventing fluid from entering the pump. Continued
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41. Figure 44–17 Washer pumps usually install into the reservoir and are held in place with a retaining ring.
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47. Figure 44–20 A typical squirrel cage blower motor. A replacement blower motor usually does not come equipped with the squirrel cage blower, so it has to be switched from the old motor. Continued
48. Figure 44–21 Typical blower motor resistors used to control blower motor speed. Continued
49. Figure 44–22 A brushless DC motor that uses the body computer to control the speed. (Courtesy of Sammy’s Auto Service, Inc.)
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52. Figure 44–23 A typical blower motor circuit with four speeds. The three lowest fan speeds (low, medium-low and medium-high) use the blower motor resistors to drop the voltage to the motor and reduce current to the motor. On high, resistors are bypassed. The “high” position on the fan switch energizes a relay, which supplies current for the blower on high through a fusible link. Continued
53. Figure 44–24 Using a mini AC/DC clamp-on multimeter to measure the current draw of a blower motor. Continued
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56. NOTE: If the high-speed fuse blows a second time, check the current draw of the motor and replace the blower motor if the current draw is above specifications. Check for possible normal operation if the rear-window defogger is not in operation; some vehicles electrically prevent simultaneous operation of the high-speed blower and rear-window defogger to help reduce the electrical loads.
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