How do I check the cruise control switch?
 

I want to find out if my cruise control switch is OK before putting in more expensive parts.
I did a conductivity test on it and these are my results.

Pin combination Conductivity Lever Position
1-2 Yes Neutral, Off, Resume, Accel. Set, Decel.Set
1-3 Yes Decel. Set
1-4 Yes Accel. Set
1-5 Yes Resume
2-3 Yes Decel. Set
2-4 Yes Accel. Set
2-5 Yes Resume
3-4 No
3-5 No
4-5 No

I’d like to know are these readings normal or do I have a short?

I cannot tell from what you have posted as it has been quite a long time since i was working on my cruise control. I would suggest that you go to http://gdl-online.com where you will find very good instructions for checking out your CC before you go blowing alot of money guessing. Don

I looked at the site and I'll check it tomorrow.

Answer
 

Cruise Control Repair Articles
http://www.peachparts.com/shopforum/diesel-discussion/123036-cruise-control-repair-articles.html#post883130

Thanks, I went to GDL's website and plan to test the system in the morning. Unless work gets in the way.

Does the linked info cover the W124?

The '87 has no CC. Not sure what to check first.
The tach is inop if that means anything for this purpose.

Well I checked the CC circuit per GDL and it appears that the actuator motor is shot. The ohms readings between pin 9&12 and 9&13 was infinity not 3.4K and 0 ohm as per spec.
The motor test failed completely. It was supposed to read 130 - 180 mAdc but I got 0.00 and no sound from the actuator.
Guess It's a off to the shop for my actuator and amp. Better get to work so I can pay for it.

The GDL guy is as nice if not even nicer (is that possible?) than the guys here on this site. His name is peter, and he is awesome. Incredibly helpful.