Servo Electrical Tests

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:

Fig. 83 Servo Terminal Electrical Connections:

1983-87 REAR WHEEL DRIVE MODELS

1. Connect a suitable test lamp between yellow wire and ground, then proceed as follows:
a. Place speed control switch and ignition switch in "On" position. Test lamp should illuminate.
b. Depress "Set" button. Test lamp should go out and a clicking noise should be heard at servo.
c. Release "Set" button. Test light should illuminate and another click should be heard at servo.
d. If test results are not satisfactory, possible causes may be a blown fuse, faulty wiring or defective speed control switch or servo.
2. Connect a suitable test lamp between white wire and ground, then proceed as follows:
a. Place speed control switch and ignition switch in "On" position. Test lamp should be off.
b. Depress "Set" button. Test lamp should illuminate.
c. If test results are not satisfactory, possible causes may be faulty wiring or defective speed control switch.
3. Connect a suitable test lamp between dark blue wire and ground, then proceed as follows:
a. Place speed control switch and ignition switch in "On" position. Test lamp should illuminate.
b. If test result is not satisfactory, possible causes may be faulty wiring or defective brake, clutch, or speed control switches.