* PLEASE READ THIS FIRST *

NOTE: This is GENERAL information. This article is not intended to be specific to any unique situation or individual vehicle configuration. The purpose of this Troubleshooting information is to provide a list of common causes of problem symptoms. For model-specific Troubleshooting, refer to SUBJECT, DIAGNOSTIC, or TESTING articles available in the section(s) you are accessing.


  ACCESSORIES & ELECTRICAL

CHARGING SYSTEM TROUBLESHOOTING

BASIC CHARGING SYSTEM TROUBLESHOOTING CHART

CONDITION & POSSIBLE CAUSE CORRECTION
Vehicle Will Not Start
Dead battery Check battery cells, alternator belt tension and alternator output
Loose or corroded battery connections Check all charging system connections
Ignition circuit or switch malfunction Check and replace as necessary
Alternator Light Stays On With Engine Running
Loose or worn alternator drive belt Check alternator drive tension and condition, See Belt Adjustment in TUNE-UP article in the TUNE-UP section
Loose alternator wiring connections Check all charging system connections
Short in alternator light wiring See Indicator Warning Lights in STANDARD INSTRUMENTS in the ACCESSORIES & EQUIPMENT section
Defective alternator stator or diodes See Bench Tests in ALTERNATOR article
Defective regulator See Regulator Check in ALTERNATOR article
Alternator Light Stays Off With Ignition Switch ON
Blown fuse See WIRING DIAGRAMS
Defective alternator See Testing in ALTERNATOR article
Defective indicator light bulb or socket See Indicator Warning Lights in STANDARD INSTRUMENTS in the ACCESSORIES & EQUIPMENT section
Alternator Light Stays OFF With Ignition Switch ON
Short in alternator wiring See On-Vehicle Tests in ALTERNATOR article
Defective rectifier bridge See Bench Tests in ALTERNATOR article
Lights or Fuses Burn Out Frequently
Defective alternator wiring See On-Vehicle Tests in ALTERNATOR article
Defective regulator See Regulator Check in ALTERNATOR article
Defective battery Check and replace as necessary
Ammeter Gauge Shows Discharge
Loose or worn drive belt Check alternator drive belt tension and condition. See Belt Adjustment in TUNE-UP article in the TUNE-UP section
Defective wiring Check all wires and wire connections
Defective alternator or regulator See Bench Tests and On-Vehicle Tests in ALTERNATOR article
Defective ammeter, or improper ammeter wiring connection See Testing in STANDARD INSTRUMENTS in the ACCESSORIES & EQUIPMENT section
Noisy Alternator
Loose drive pulley Tighten drive pulley attaching nut
Loose mounting bolts Tighten all alternator mounting bolts
Worn or dirty bearings See Bearing Replacement ALTERNATOR article
Defective diodes or stator See Bench Test in ALTERNATOR article
Battery Does Stay Charged
Loose or worn drive belt Check alternator drive belt tension and condition. See Belt Adjustment in appropriate TUNE-UP article in the TUNE-UP section
Loose or corroded battery connections Check all charging system connections
Loose alternator connections Check all charging system connections
Defective alternator or battery See On-Vehicle Tests and Bench Tests in ALTERNATOR article
Add-on electrical accessories exceeding alternator capacity Install larger alternator
Battery Overcharged-Uses Too Much Water
Defective battery Check alternator output and repair as necessary
Defective alternator See On-Vehicle Test and Bench Tests in ALTERNATOR article
Excessive alternator voltage Check alternator output and repair as necessary

Dennis N.

Dodge, Durango

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