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Cruise Control Module: Testing and Inspection


Use only a multi-meter of 5000 ohm/volt rating or higher when performing amplifier test.
``On'' Circuit Test
1. Turn ignition ``On.''
2. Connect a voltmeter between light blue wire w/black hash and ground on models exc. 1983-87 Ranger, 1984-87 Bronco II and 1986-87 Aerostar or white wire w/purple stripe and ground on 1983-87 Ranger, 1984-87 Bronco II and 1986-87 Aerostar.
3. Battery voltage should be indicated when ``On'' switch on steering column is depressed and held. If battery voltage is not indicated, check horn relay and perform control switch test.
4. Release ``On'' button. Voltmeter should indicate 7.8 volts indicating ``On'' circuit is engaged. If voltage does not remain, check amplifier ground, fuses or circuit breakers or replace amplifier with known good amplifier and repeat test.
5. Replace as necessary.
``Off'' Circuit Test
1. Turn ignition ``On.''
2. Connect a voltmeter between light blue wire w/black hash and ground.
3. Depress ``Off'' button. Voltage should drop to zero indicating ``On'' circuit is de-energized.
4. If voltage does not drop to zero, perform ``Control Switch Test.''
``Set-Accelerate'' Circuit Test
1. Turn ignition ``On.''
2. Connect a voltmeter between light blue wire w/black hash and ground.
3. Depress ``On'' switch, then hold ``Set-Accel'' button on steering wheel. Voltmeter should indicate 4.5 volts. Rotate steering wheel back and forth and check for voltmeter fluctuations. If reading varies more than .5 volts, perform ``Control Switch Test.''
``Coast'' Circuit Test
1. Turn ignition ``On.''
2. Connect a voltmeter between light blue wire w/black hash and ground.
3. Depress ``On'' switch, then depress and hold ``Coast'' button on steering wheel. Voltmeter should indicate 1.5 volts. Rotate steering wheel back and forth and check for voltage fluctuations. If reading varies more than .5 volts, perform ``Control Switch Test.''
``Resume'' Circuit Test
1. Turn ignition ``On.''
2. Connect a voltmeter between light blue wire w/black hash and ground.
3. Depress and hold ``Resume'' button. Voltmeter should indicate 6.5 volts. If all circuits are functioning properly, perform ``Servo Assembly Test'' using a known good amplifier. Do not replace amplifier before performing servo test.