Ignition "OFF" & Engine "OFF".

Check belt tension for alternator.

Check Battery terminal, Fusible Link and Alternator B+ for poor connection and corrosion.

Ignition "ON" & Engine "ON".

Turn ON electrical Load such as Head Lamp, Blower Motor and Defroster.

Measure battery voltage when engien is more than 2000 rpm.

Specification : 12.5 ~ 14.5V

Is the measured voltage within specifications ?

YES

▶ Substitute with a known-good ECM and check for proper operation.

If the problem is corrected, replace ECM and then go to "Verification of Vehicle Repair" procedure.

NO

▶ Check height and condition of Brake switch. Substitute with a known-good Brake switch and check for proper operation. If the problem is corrected, replace Brake switch and then go to "Verification of Vehicle Repair" procedure.