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Undercharged Or Overcharged Battery

NOTE: Ensure battery is fully charged and in good condition before performing the following steps. If battery is not at (or near) a fully charged condition, or if its condition is questionable, substitute a known good battery before proceeding.
  1. On all models except Achieva, perform test procedures under the appropriate VEHICLES WITH CHARGE/CHECK GAUGES WARNING LIGHT  or VEHICLES WITH GAUGES  headings. Disconnect alternator connector. Turn ignition on. Using a DVOM, connect positive voltmeter lead to Pink/Black or Brown wire and negative lead to ground.
  2. Battery voltage should be present. If battery voltage is not present, check and repair circuit No. 639 (Pink/Black) or circuit No. 250 (Brown wire) for an open or short to ground. Check fuses, replace if necessary.
  3. Connect positive voltmeter lead to battery terminal of alternator and negative lead to ground. Battery voltage should be present. If battery voltage is not present, check and repair Black/Red or Red wire from battery to alternator for an open or short to ground.
  4. On models with 3.3L engine, connect positive voltmeter lead to Red wire and negative lead to ground. Battery voltage should be present. If battery voltage is not present, check for an open in circuit No. 2 (Red wire) and fusible link for an open.
  5. With engine running at fast idle speed and all accessories turned off, voltmeter should read greater than 12 volts and less than 16 volts. If voltmeter indicates greater than 16 volts or less than 12 volts, repair or replace alternator.
  6. On Achieva, disconnect alternator battery terminal and alternator electrical connector. Turn ignition on. Measure voltage between terminal "L" (Brown wire) and ground. Battery voltage should be present.
  7. If battery voltage is not present, check and repair open in circuit No. 25 (Brown wire) and circuit No. 39 (Pink/Black wire). If battery voltage is present, turn ignition on. Measure voltage between terminal "F" (Pink/Black wire) and ground.
  8. Battery voltage should be present. If battery voltage is not present, check fuses and repair open in circuit No. 439 (Pink/Black wire). If battery voltage is present, with ignition on, measure voltage between terminal "S" (Red wire) and ground.
  9. Battery voltage should be present. If battery voltage is not present, repair open in circuit No. 2 (Red wire). If battery voltage is present, with ignition switch on, measure voltage between BAT terminal (Red wire) and ground.
  10. Battery voltage should be present. If battery voltage is not present, repair open in circuit No. 2 (Red wire). If battery voltage is present, reconnect alternator electrical connector.
  11. Turn all accessories off. With engine running, measure voltage between BAT terminal (Red wire) and ground. Voltage should be less than 16 volts. If voltage is greater than 16 volts, repair or replace alternator. If voltage is okay, see CURRENT OUTPUT TEST .
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