2000 Mazda B2500 SX, AutomaticFACTORY OEM SERVICE PROCEDURE

Charging System Symptom Chart: Notes

CHARGING SYSTEM SYMPTOM CHART

Problem Possible Cause Action
  • The Charging System Warning Indicator is ON with the Engine Running (The Battery Voltage Does Not Increase)
  • (W/B) wire.
  • (Y) wire.
  • B+ (Y/W) wire.
  • B+ mega fuse.
  • (LG/R) wire.
  • Voltage regulator.
  • Generator.
 See PINPOINT TEST 1: THE CHARGING SYSTEM WARNING INDICATOR IS ON WITH THE ENGINE RUNNING (BATTERY VOLTAGE DOES NOT INCREASE) .
  • The Charging System Warning Indicator is OFF with the Ignition Switch in the ON Position and the Engine OFF (Battery Voltage Does Not Increase)
  • Voltage regulator connector.
  • (LG/R) wire.
  • Fuse 15 (7.5A)
  • Voltage regulator.
  • Loose or damaged generator.
  • Harness connector.
 See PINPOINT TEST 2: THE CHARGING SYSTEM WARNING INDICATOR IS OFF WITH THE IGNITION SWITCH IN THE ON POSITION AND THE ENGINE OFF (BATTERY VOLTAGE DOES NOT INCREASE) .
  • The Charging System Warning Indicator is ON with the Engine Running and the Battery Voltage Increases
  • (W/B) wire.
  • Generator.
  • Voltage regulator.
 See PINPOINT TEST 3: THE CHARGING SYSTEM WARNING INDICATOR IS ON WITH THE ENGINE RUNNING AND THE BATTERY VOLTAGE INCREASES .
  • The Charging System Warning Indicator is OFF with the Ignition Switch in the ON Position and the Engine OFF (Battery Voltage Increases)
  • Charging system warning indicator bulb.
  • Instrument cluster.
  • (W/B) wire.
  • Generator.
  • Voltage regulator.
 See PINPOINT TEST 4: THE CHARGING SYSTEM WARNING INDICATOR IS OFF WITH THE IGNITION SWITCH IN THE ON POSITION AND THE ENGINE OFF (BATTERY VOLTAGE INCREASES) .
  • The Charging System Warning Indicator Operates Correctly but the Battery Voltage Does Not Increase
  • B+ (Y/W) wire.
  • B+ mega fuse.
  • Loose or damaged harness connector.
  • Battery cables.
  • Generator.
  • Voltage regulator.
 See PINPOINT TEST 5: THE CHARGING SYSTEM WARNING INDICATOR OPERATES CORRECTLY BUT THE BATTERY VOLTAGE DOES NOT INCREASE .
  • The Battery is Dead or Will Not Stay Charged or Low Battery or Generator Voltage
  • Corroded terminal(s).
  • Loose connection(s).
  • High key-off load.
  • Generator.
  • Voltage regulator.
 See PINPOINT TEST 6: THE BATTERY IS DEAD OR WILL NOT STAY CHARGED OR LOW BATTERY OR GENERATOR VOLTAGE .
  • The System Overcharges (Battery Voltage Greater Than 15.5 Volts)
  • (W/B) wire.
  • Generator (low output).
  • Voltage regulator.
  • (LG/R) wire.
 See PINPOINT TEST 7: THE SYSTEM OVERCHARGES (BATTERY VOLTAGE GREATER THAN 15.5 VOLTS) 
  • Battery Leakage or Damage
  • (W/B) wire.
  • Generator.
  • Voltage regulator.
  • Battery.
 See PINPOINT TEST 8: BATTERY LEAKAGE OR DAMAGE .
  • The Generator is Noisy
  • Loose bolts/brackets.
  • Drive belt.
  • Generator/pulley.
 See PINPOINT TEST 9: THE GENERATOR IS NOISY .
  • Radio Interference
  • Generator
  • Wiring/routing.
  • In-vehicle entertainment system.
 See PINPOINT TEST 10: RADIO INTERFERENCE .
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Stop DIY work and contact a certified mechanic immediately if any of the following apply:

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  • • The engine overheats, stalls repeatedly, or misfires under load.
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