Voltage Regulator Dodge Aries I

DESCRIPTION

The electronic voltage regulator regulates electrical system voltage by limiting output voltage generated by alternator. This is accomplished by controlling amount of current allowed to pass through alternator field winding.

The regulator has no moving parts and requires no adjustment after being set at factory. This unit contains several semiconductor components, transistors and diodes, plus some resistors and a capacitor.

A large transistor is placed in series with alternator field winding and control circuit which senses system voltage and turns transistor on and off as required. As alternator speed and electrical system load conditions change, control circuit is turning transistor on and off many times per second most of the time engine is in operation.

The only time transistor is not turning on and off rapidly is during low engine speed operation when high electrical loads are present (which require alternator field to be in the on state continuously).

The electronic voltage regulator control circuit can also vary regulated system voltage up or down as temperature changes.

ADJUSTMENTS

The electronic voltage regulator cannot be adjusted. If specifications are not obtained and investigation has proved that the rest of the electrical system is not at fault, regulator must be replaced.

TROUBLE SHOOTING

Note. See the TROUBLE SHOOTING - BASIC PROCEDURES article in the GENERAL TROUBLE SHOOTING section.

TESTING

Note. Battery specific gravity should be above 1.220 for a proper regulated voltage check. Charge battery or use a good test battery before testing regulator. DO NOT leave uncharged battery in circuit.

Scheme 1

1. Connect positive lead of voltmeter to positive post on battery. Connect negative lead from voltmeter to good vehicle body ground. (Scheme 1) (Scheme 1): Meter Connections for Voltage Regulator Tests Check voltage regulator for good ground.
2. Connect tachometer to engine. Start and run vehicle at 1250 RPM with all lights and accessories turned off. Check voltmeter. Regulator is working properly if voltage readings are within specifications. NOTE: It is normal for vehicle ammeter to show immediate charge and then gradually return to normal position. The duration that ammeter needle remains in high charge range depends on length of cranking time.
3. If voltage is below limits or is fluctuating, check that regulator has good ground. Regulator ground is obtained through regulator case, to mounting screws and to sheet metal of vehicle. Check this ground circuit for opens.
4. With ignition switch in "OFF" position, disconnect regulator connector. NOTE: Be sure terminals of connector have not spread open to cause open or intermittent connection. DO NOT start engine or distort terminals with voltmeter probe.
5. Turn ignition switch to "ON" position (but DO NOT start engine). Check for battery voltage at wiring harness terminal.
6. Battery voltage should appear at both Blue and Green leads of connector. If all tests are satisfactory, replace regulator and repeat test.
7. If voltage regulator is above limits shown on chart, proceed as follows.
8. Turn ignition switch to "OFF" position and disconnect regulator connector. Be sure terminals on connector have not spread open.
9. Turn ignition switch to "ON" position (but DO NOT start engine) and check for battery voltage at wiring harness terminal.
10. Both Green and Blue leads should read battery voltage. Turn ignition switch to "OFF" position.
11. If previous tests are satisfactory, replace regulator and repeat test. Remove voltmeter and tachometer.

SPECIFICATIONS

ELECTRONIC VOLTAGE REGULATOR SPECIFICATIONS

See also:
• TROUBLE SHOOTING - BASIC PROCEDURES