2. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 OBJECTIVES After studying Chapter 7, the reader should be able to: 1.Prepare for ASE Electrical/Electronic Systems (A6) certification test content area “A” (General Electrical/Electronic System Diagnosis). 2.Identify a series-parallel circuit. 3.Calculate current flow and voltage drops in a series-parallel circuit. 4.Identify where faults in a series-parallel circuit can be detected or determined.

3. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 SERIES-PARALLEL CIRCUITS Series-parallel circuits are a combination of series and parallel segments in one complex circuit. A series-parallel circuit includes both parallel loads or resistances, plus additional loads or resistances that are electrically connected in series.

4. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 SERIES-PARALLEL CIRCUITS A circuit where the load is in series with other loads is parallel. FIGURE 7-1 A series-parallel circuit.

5. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 SERIES-PARALLEL CIRCUITS A circuit where a parallel circuit contains resistors or loads are in series in one or more branches. FIGURE 7-2 This complete headlight circuit with all bulbs and switches is a series-parallel circuit.

6. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 SERIES-PARALLEL CIRCUITS Series-Parallel Circuit Faults If a conventional parallel circuit, such as a taillight circuit, had an electrical fault that increased the resistance in one branch of the circuit, then the amount of current flow through that one branch will be reduced.

7. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 SOLVING SERIES-PARALLEL CIRCUIT PROBLEMS The key to solving series-parallel circuit problems is to combine or simplify as much as possible. FIGURE 7-3 Solving a series-parallel circuit problem.

8. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 SERIES-PARALLEL CIRCUIT EXAMPLES Each of the four examples includes solving for the following: –Total resistance –Current flow (amperes) through each branch, as well as total current flow –Voltage drop across each resistance

9. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 SERIES-PARALLEL CIRCUIT EXAMPLES FIGURE 7-4 Example 1.

10. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 SERIES-PARALLEL CIRCUIT EXAMPLES FIGURE 7-5 Example 2.

11. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 SERIES-PARALLEL CIRCUIT EXAMPLES FIGURE 7-6 Example 3.

12. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 SERIES-PARALLEL CIRCUIT EXAMPLES FIGURE 7-7 Example 4.

13. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 SUMMARY 1.A series-parallel circuit is called a compound circuit or a combination circuit. 2.A series-parallel circuit is a combination of a series and a parallel circuit, which does not include fuses or switches. 3.A fault in a series portion of the circuit would affect the operation if the series part was in the power or the ground side of the parallel portion of the circuit. 4.A fault in one leg of a series-parallel circuit will affect just the component(s) in that one leg.

14. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 REVIEW QUESTIONS 1.Explain why an increase in resistance in the series part of a series-parallel circuit will affect the current (amperes) through the parallel legs (branches). 2.What would be the effect of an open circuit in one leg of a parallel portion of a series-parallel circuit? 3.What would be the effect of an open circuit in a series portion of a series-parallel circuit?

15. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 CHAPTER QUIZ 1.Half of the dash is dark. Technician A says that a defective dash light dimmer can be the cause because it is in series with the bulbs that are in parallel. Technician B says that one or more bulbs could be defective. Which technician is correct? a)Technician A only b)Technician B only c)Both Technicians A and B d)Neither Technician A nor B

16. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 CHAPTER QUIZ 2.All brake lights are dimmer than normal. Technician A says that bad bulbs could be the cause. Technician B says that high resistance in the brake switch could be the cause. Which technician is correct? a)Technician A only b)Technician B only c)Both Technicians A and B d)Neither Technician A nor B

17. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 CHAPTER QUIZ 3.See Figure 7-8 to solve for total resistance (R T ) and total current (I T ). a)10 ohms ÷ 1.2 A b)4 ohms ÷ 3 A c)6 ohms ÷ 2 A d)2 ohms ÷ 6 A FIGURE 7-8 Chapter quiz question 3.

18. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 CHAPTER QUIZ 4.See Figure 7-9 to solve for the value of R 3 and total resistance (R T ). a)12 ohms ÷ 12 ohms b)1 ohm ÷ 7 ohms c)2 ohms ÷ 8 ohms d)6 ohms ÷ 6 ohms FIGURE 7-9 Chapter quiz question 4.

19. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 CHAPTER QUIZ 5.See Figure 7-10 to solve for voltage (E ) and total resistance (RT). a)16.3 volts ÷ 12 ohms b)3.3 volts ÷ 2.4 ohms c)1.36 volts ÷ 1 ohm d)6 volts ÷ 4.4 ohms FIGURE 7-10 Chapter quiz question 5.

20. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 CHAPTER QUIZ 6.See Figure 7-11 to solve for R1 and total resistance (RT). a)3 ohms ÷ 15 ohms b)1 ohm ÷ 15 ohms c)2 ohms ÷ 5 ohms d)5 ohms ÷ 5 ohms FIGURE 7-11 Chapter quiz question 6.

21. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 CHAPTER QUIZ 7.See Figure 7-12 to solve for total resistance (RT) and total current (I ). a)3.1 ohms ÷ 7.7 amperes b)5.1 ohms ÷ 4.7 amperes c)20 ohms ÷ 1.2 amperes d)6 ohms ÷ 4 amperes FIGURE 7-12 Chapter quiz question 7.

22. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 CHAPTER QUIZ 8.See Figure 7-13 to solve for the value of E and total resistance (RT). a)13.2 volts ÷ 40 ohms b)11.2 volts ÷ 34 ohms c)8 volts ÷ 24.2 ohms d)8.6 volts ÷ 26 ohms FIGURE 7-13 Chapter quiz question 8.

23. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 CHAPTER QUIZ 9.See Figure 7-14 to solve for total resistance (RT) and total current (I ). a)1.5 ohms ÷ 8 amperes b)18 ohms ÷ 0.66 ampere c)6 ohms ÷ 2 amperes d)5.5 ohms ÷ 2.2 amperes FIGURE 7-14 Chapter quiz question 9.

24. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 CHAPTER QUIZ 10.See Figure 7-15 to solve for total resistance (RT) and total current (I ). a)48 ohms ÷.42 ampere b)20 ohms ÷ 1 ampere c)30 ohms ÷.66 ampere d)10.2 ohms ÷ 1.96 amperes FIGURE 7-15 Chapter quiz question 10.

25. Automotive Electricity and Electronics, 2/e By James D Halderman © 2009 Pearson Education, Inc. Pearson Prentice Hall - Upper Saddle River, NJ 07458 END