Service Tips for 1989 Honda Civic Part Ill Courtesy Honda Motor Co. Charging System Description To improve the fuel economy, this system changes the voltage generated at the alternator in accordance with the driving conditions. Alternator and Regulator Test First make sure you have a good battery, and that the alternator belt and connections at the alternator and main fuses are good. Next check the no. 14 (10A) fuse in the dash fuse box. (If blown, the charge warning light will come on even if the system’s working properly.) Start the engine and allow it to warm up (cooling fan comes on). Disconnect the alternator connector | | ) Throttle angle sensor i | | ——————— Coolant temperature sensor rr ae | ] Intake air temperature sensor —_— Starter switch signal | } | TDC/CRANK sensor ——__+ Speed sensor Brake switch signal ed | — ELD Air conditioning signal — ECU Si pee – STARTER SWITCH ON AND GENERATED VOLTAGE DECREASES FROM 14.5V TO 12.5V AND ELECTRICAL LOAD BELOW 10A and VEHICLE SPEED BELOW 65 km/h and ENGINE SPEED BELOW 3,600 rpm | and | COOLANT TEMPERATURE ABOVE 60° (140’F) and A/C SWITCH OFF | and | INTAKE AIR TEMPERATURE ABOVE 18’C (65°F) BRAKE SWITCH OFF TROL FUNCTION IS NOT PERFORMED Ee CUT-OFF CON- | from the alternator. With the ignition switch on, there should be battery voltage between the IG (BLK/YEL) terminal and body ground. If there is no voltage check for: Blown no. 14 (10A) fuse in the dash fuse box; or an open in the BLK/YEL wire between the dash fuse box the voltage regulator. If there is battery voltage, go to the next step. View from Connect the voltmeter positive probe feurint si IG (BLK/YEL} MAIN FUSE BOX. BATTERY No, 31 (608) ) No. 32 (50A) | = a GRN/RED BLK/YEL CHARGE Oise LIGHT (1.4W) PGM-FI ECU PGM-FI ECU WHT/BLU ALTERNATOR Q 8! eee Re ALTERNATOR (Mitsubishi type)