Charging System Diagnosis February, 2005

SYMPTOMS CAUSES AND SOLUTIONS
(SEE CHART BELOW)

No indicator light on dash -ignition switch on
1, 2, 3, 4, 5, 6

Indicator light remains on with engine running
1, 7, 8, 9

Battery discharges
7, 8, 9, 10, 11, 12

Alternator overcharges
4, 5, 13

Noisy alternator
7, 14, 15, 16

Overcharged battery
1, 4, 5, 17

No output
1, 4, 5, 7, 12, 13, 17



PROBABLE CAUSES POSSIBLE SOLUTIONS


#1 Defective fuse*Replace

#2 Defective bulb*Replace

#3 Bad wiring or loose connection*Repair as necessary

#4 Defective regulator (external regulator)*Replace

#5 Defective regulator (internal regulator)*Replace alternator

#6 Rotor not energized*Replace alternator

#7 Belts worn, loose, or too tight*Check tension or replace*Check belt tensioner for proper operation

#8 Battery cables loose/corroded*Clean/tighten or replace

#9 Defective fusible link*Replace

#10 Defective battery*Load test, charge, or replace

#11 Excessive draw*Test and repair

#12 Bad ground circuit*Check negative battery cable and connections*Check engine ground straps

#13 Damaged sense wire*Identify and repair

#14 Loose mounting bolts*Check and tighten

#15 Loose alternator fan and/or pulley*Check and tighten

#16 Defective alternator bearings*Replace alternator

#17 Wiring harness shorted*Diagnose and repair