Cruise Control Switch: Testing and Inspection

1980-87 Models Exc. 1983-87 Ranger, 1984-87 Bronco II & 1986 Aerostar
Disconnect 6 way connector from control switch at the amplifier, then perform the following checks:
1. Connect a voltmeter between light blue-black hash lead and ground, then depress the ``On'' button and check for battery voltage.
2. Turn ignition ``Off,'' then connect an ohmmeter between light blue-black hash lead and ground.
3. Rotate steering wheel throughout its full range while making the following checks:
a. Depress ``Off'' button and check for a reading of 0-1 ohm.
b. Depress ``Set'' button and check for a reading of 646-714 ohms.
c. Depress and hold ``Coast'' switch and check for a reading of 114-126 ohms.
d. On models with ``Resume,'' depress and hold ``Resume'' switch and check for a reading of approximately 2200 ohms.
4. If resistance values are not as specified, inspect wiring, slip rings, turn signal copper brushes, speed control switch and steering column for proper ground. Check for proper ground by connecting an ohmmeter between upper steering column flange and a suitable ground. Resistance should be less then 1/2 ohm. Rotate steering wheel throughout its full range and ensure flexible coupling has a resistance of less than 1 ohm.



1983-87 Ranger, 1984-87 Bronco II & 1986-87 Aerostar
1. Check main fuse and stop lamp fuse and replace as necessary, then remove steering wheel cover.
2. With ignition ``Off,'' connect an ohmmeter between purple wire w/orange stripe and black wire of steering wheel connector, then depress ``On'' switch and check for a reading of 0-1 ohms.
3. If reading is not correct, replace switch assembly, then clean brush assembly and slip rings in a suitable solvent and lubricate with a suitable lubricant.
4. With ignition switch ``Off,'' connect an ohmmeter between light blue-black hash wire and black wire of steering wheel connector, then depress the following switches and check for the following values:
a. ``Off,'' 0-1 ohm.
b. ``Set/Accel,'' 646 to 714 ohms.
c. ``Coast,'' 114-126 ohms.
d. ``Resume,'' 2090-2310 ohms.
5. If values are not correct, clean and lubricate brushes and slip rings, then replace switch.
6. With ignition ``Off,'' connect a voltmeter between blue wire w/black hash and black wire of steering wheel connector, then proceed as follows:
a. Turn ignition ``On'' and check for a reading of 7.8 volts.
b. Depress ``On'' switch and check for a reading of 12 volts.
c. If voltage checks are satisfactory, switches and wiring are working properly. If voltages are not satisfactory, turn ignition ``Off'' and proceed to step 7.
7. Disconnect ground brush from wiring harness, then connect an ohmmeter between white wire w/purple stripe and black wires at brush assembly pigtail. Depress ``On'' switch and check for a reading of 0-1 ohms while rotating steering wheel throughout its full range.
8. Connect an ohmmeter between light blue wire w/white stripe and black wires at brush assembly pigtail, then check for resistance values previously described in step 4.
9. If fluctuations occur in readings while rotating steering wheel throughout its travel, clean and lubricate brushes and slip rings, then install steering wheel and repeat steps 7 and 8.
10. If no resistances are read, replace ground brush assembly, clean and lubricate slip rings, then reinstall steering wheel and repeat steps 7 and 8.
11. If resistances are correct and no fluctuations occur while turning steering wheel, ground brushes and slip rings are satisfactory. If replacement of switch assembly and/or ground brush assembly does not produce correct values, check slip rings for shorts. If necessary, replace entire wheel assembly, then repeat steps 7 and 8.