Alternator Output Test
- Remove alternator connector. Turn ignition switch to "ON" position. There should be battery voltage between "IGN" (Black/Yellow) terminal and ground.
- On Integra, check for a blown No. 4 fuse or an open in Blue/Yellow wire between dash fuse box and voltage regulator.
- Connect voltmeter positive lead to positive battery terminal and negative lead to alternator "C" connector (Blue wire on Integra). Start engine and turn all accessories off. If battery voltage is present, go to next step. If no voltage is present, check for an open in Blue wire, between voltage regulator and Electronic Control Unit (ECU).
- Turn headlights on. If no voltage is present, go to next step. If battery voltage is present, check for a short-to-ground in Blue wire from voltage regulator to ECU or defective ECU.
- Test system using an alternator tester with an integral carbon pile. Operate engine at 2000 RPM and ensure cooling fan is off. Apply a load with carbon pile so voltage drops to no less than 12 volts. Check maximum amperage and compare with specifications on chart. See Fig 1.
- If amperage is within specification, charging system is okay. If amperage is not within specification, do a full-field test.CAUTION: Ground screwdriver for as short a time as possible. Do not exceed maximum recommended voltage of 16 volts.
- On Integra models, check "IG" (Black/Yellow) wire for battery voltage and "C" (Blue) wire for short-to-ground. If alternator and wiring are okay, replace voltage regulator.