Brake Switch (Cruise Control): Testing and Inspection

Refer to "Speed Control Wiring Diagrams". Prior to performing any tests, ensure servo or valve body and electronic module are properly tested.

Fig. 2 Speed control wiring diagram. 1980-84 Vans, Wagons & Front Sections:

Fig. 3 Speed control wiring diagram. 1981-84 Ramcharger, Trail Duster & Conventional Cabs:

Fig. 4 Speed control wiring diagram. 1982-84 Rampage & 1983 Scamp:

Fig. 5 Speed control wiring diagram. 1984 Mini-Vans/Wagons (1985 similar):

Fig. 6 Speed control wiring diagram. 1985 Conventional Cabs & Ramcharger:

Fig. 7 Speed control wiring diagram. 1985 rear wheel drive Ram Van & Wagons:

Fig. 8 Speed control wiring diagram. 1986-87 Conventional Cabs & Ramchargers:

Fig. 9 Speed control wiring diagram. 1986 rear wheel drive Ram Van & Wagons:

Fig. 10 Speed control wiring diagram. 1986 Mini-Vans/Wagons:

1986-87 Mini-Vans/Wagons

1. Connect negative lead of a voltmeter to chassis ground.
2. Turn ignition switch and speed control switch to On position.
3. Check for 12 volts at blue and blue/red wires of stop lamp switch electrical connector. If 12 volts is indicated at only one one terminal, actuate brake pedal and ensure a click is heard just before pedal reaches return stop. If click is not heard, adjust or replace switch as necessary. If no voltage is indicated at either terminal, check condition of speed control fuse and replace if necessary.
4. Measure voltage at pin No. 4 of electronic module electrical connector. Voltmeter should indicate .5 volt with brake pedal fully released and 12 volts with brake pedal depressed and the brake lights illuminated. If voltage readings are not as specified, check brake lamp circuit fuse, brake lamps, clutch switch and brake switch adjustment and make necessary repairs and/or adjustments.