cruise control

[Hitchner2009]

so i have been working on my cruise control all day and i have yet to get it working. i have tested voltages at the switches, the buttons(steering wheel control) all my lights work. Idk what the problem is, the relay is good, idk how to test or find the amplifier, this chilton manual says barely anything on cruise control. i have 11-12 volts at the clutch switch and brake switch. but when i apply them, using the pedal, all voltage drops, idk if this is normal or not. i have 12 volts with the on button for the cruise control depressed and about 7-8 volts when i hit the set accel buttons. All my brake lights, and signals work. I believe the servo to be good, it holds good vacuum. idk what else to do, nobody seems to answer my question for cruise control on here. i have a 1987 Ford Ranger XLT super cab 2.9l v6 4x4 5-speed. PLEASE HELP!!

 

[monsterchuck]

Well, you've gone through and checked the entire system except for the amplifier itself, and if you don't see any other glaring problems, it might be time to put a new one on. See if you can snag one in a junkyard so you don't drop too much cash in case that isn't it.