Cadillac Repair: 1982 Cadillace DeVille Sentinel Headlights, cadillace, fusible links

Question
The running/parking lights work fine when you pull the headlight switch on to either position (running lights or headlights), but the headlights will not turn on.  I have checked and replaced the manual part of the headlight switch, but still no headlights even with playing with the sentinel knobs.  I have also checked at least one headlight bulb to see that it is not burned out so it is not burned headlights causing the problem.  

Questions:
1. Does the sentinel controller that is located under the dash somewhere control the manual part of the headlights too?

2. Where is this controller located?  Is there a way to test it?

3. Is there a relay in the system somewhere to control the headlights?

Answer
First check the fusible links at the battery terminal on the starter. There are 2 or 3 rubber covered wires that are about 4 inches long and then they turn into plastic covered inside of the plastic ribbed electrical wires covering.

Test these links by probing the links up where they turn into plastic covering and see if you have battery voltage on all the thru all these rubber covered links.

If you find one that does NOT have battery voltage running thru it, You can purchase replacement links at any auto parts store.