Charging System - Diagnosis

87yugo01

NUMBER: 7-03

DATE: 4/22/87
SUBJECT: CHARGING SYSTEM

VEHICLES: YUGO GV -- ALL

DISTRIBUTION: All Dealer Service Departments
GENERAL
INFORMATION: The charging system is suspect in the following complaints:

1. No start - doesn't crank
2. Hard starting - cranks slowly
3. Lights flickering or dim - battery goes dead
4. Repeated bulb failure
5. Charge indicator light flickers or stays on

Before removing the alternator, check the following:

1. Alternator belt tension and condition
2. Battery terminal connections
3. Positive cable connection at starter
4. Ground cable connections on engine and body
5. Battery fluid level and specific gravity of each battery cell

Each of these items must be in good condition for the charging system to function efficiently.

SERVICE
INFORMATION: Use the following procedure to test the charging system.

^ Connect a voltmeter to the battery. If battery voltage is below 12 volts, charge battery before continuing.

^ Turn the ignition key to the "ON" position. If the alternator is receiving energizing current, you should feel the pull of a magnetic field when holding a screwdriver in front of the alternator pulley.

^ Start the engine and bring the speed up to 1100 rpm to achieve regulator cut-in speed. All electrical users should be off at this time.
^ Gradually increase engine speed -to 4000 rpm while watching the voltmeter. Readings should stay within the limits of 13.5 to 14.6 volts.

^ If the voltage is not within these limits, replace the regulator on car and repeat the test.

NOTE: If the voltage is less than 7 to 8 volts, then the cause is within the alternator unit. If it is over 14.8, then the problem is the regulator.