Section 14-00: Battery and Charging System, Service
1996 F-150, F-250, F-350, F-Super Duty and Bronco Workshop Manual
DIAGNOSIS AND TESTING

Symptom Chart

 

NOTE: Use Rotunda 73 Digital Multimeter 105-R0051 or equivalent to perform electrical pinpoint tests.

BATTERY AND CHARGING SYSTEM
ConditionPossible SourceAction
  • System Does Not Charge
  • Loose or worn drive belt.
  • Open/voltage drop in Circuit 38 (BK/O).
  • Open/voltage drop in Circuit 36 (Y/W).
  • Open/high resistance in Circuit 904 (LG/R).
  • Damaged regulator.
  • Damaged generator battery.
  • System Overcharges
  • Generator.
  • Regulator.
  • Indicator Light Stays On, Engine Running
  • Open A Circuit 36 (Y/W).
  • Shorted I Circuit 904 (LG/R).
  • Open/high resistance S Circuit 4 (W/BK).
  • Damaged regulator.
  • Generator.
  • Indicator Light Stays On, Ignition Switch Off
  • Shorted lamp circuit battery voltage.
  • Open A Circuit 36 (Y/W).
  • Shorted I Circuit 904 (LG/R).
  • Open/high resistance in S Circuit 4 (W/BK).
  • Instrument cluster/connector damaged.
  • Indicator Lamp Does Not Come On
  • Open in Circuit 904 (LG/R).
  • Burned-out bulb in instrument cluster.
  • Indicator Lamp Flickers/Intermittent
  • Damaged ground.
  • Damaged wiring.
  • Generator.
  • Voltage Gauge Reads High
  • Damaged regulator.
  • Charge indicator.
  • Generator.
  • Voltage Gauge Reads Low
  • Charge indicator.
  • Damaged regulator.
  • Generator.
  • Generator Noisy
  • Drive belt.
  • Generator.
  • Related components.
  • Radio Interference
  • Generator.
  • Damaged regulator.
  • Other components.
  • Battery Does Not Hold a Charge
  • Battery drain.
  • Open or high resistance in wiring.
  • Damaged regulator.
  • Generator.
MITSUBISHI 215 AMPERE GENERATOR
ConditionPossible SourceAction
  • System Does Not Charge
  • Battery connections.
  • Drive belt.
  • Battery.
  • Battery drain.
  • Open/voltage drop in B+ circuit.
  • Open A circuit.
  • Open/high resistance in I circuit.
  • Voltage regulator.
  • Generator.
  • Battery Overcharging (Battery Voltage Greater Than 15.5 V)
  • Open A circuit.
  • Poor ground.
  • Voltage regulator.
  • Generator.
  • Indicator Lamp On with Engine Running
  • Open B+ circuit.
  • Open A circuit.
  • Shorted I circuit.
  • Voltage regulator.
  • Generator.
  • Indicator Lamp Does Not Come On
  • Open/poor connection in I circuit.
  • Burned-out lamp.
  • Poor ground.
  • Voltage regulator.
  • Indicator Lamp Flickers or Intermittent
  • Loose connection at generator, megafuse, voltage regulator, battery or underhood fuse box.
  • Loose fuse or poor connection in A circuit.
  • Voltage regulator.
  • Generator.
  • Generator Noisy
  • Drive belt.
  • Accessory brackets.
  • Bent pulley or fan.
  • Generator.
  • Other accessories.
  • Radio Interference
  • Voltage regulator.
  • Generator.
  • Other components.