89 Crown Victoria - 4dr, LX, 302eng, PS, PW, PD Locks, Loaded............ Two problems seemed to arise at the same time, but could be coincidental, questionable as I have a habit of letting a problem go for awhile if not a major one.

1st problem noticed - When on "Cruise Control".... control would not release when brake pedal was pressed "Unless" speed was reduced down within the 25mph or so range. In pressing the brake pedal, the speed would drop normally, "BUT" as soon as the brake pedal was released, the speed would increase back to the preset speed. This problem has existed for about a month.

2nd problem noticed - Rather I was advised of it... Waiting at a Red Light, the driver of the car in back of me came to my window and told me that neither of my Brake Lights were operational. I removed and checked the bulbs which are okay. There is no voltage being applied to the bulbs with the brake pedal depressed. With some research, I found that the switch in mechanical, electrical but not electronical, is located under the dash to the left of the steering column. Is this switch the most likely cause of this problem?

 

Certainly check the related fuses for the lights.
Check the harness connector at the pedal switch for power distribution there. If the switch isn't active, the CC wont cancel when applying the brake.
The harness just out of the brake pedal switch like to break the wire core from flexing over time too..If the fuses check out, but no voltage at the brake switch, check the wire/s leading to the switch. A solid tug on the wire will usually stretch the covering if the core has failed..

 

Note: Hayapower.... I'm 8mts into my 90th year right now but still feel right about 48 or so, however it's a little difficult to get myself into various positions needed when working on this vehicle. Got the brake light switch ordered and will install it soon, after which I'll get back to you with success "or" what color wire is the supposed incoming voltage wire that may have broken internally?

Another problem exists (hard starting when warm) which I'll address via another entry.

 

Hi Joe,
If you don't have a decent test light to use , I would suggest you consider investing in a good one.
For the hard to reach places you can always wrap a paper clip around the test light point to extend the reach and make some checking a lot easier.

With the light,you can check fuses without pulling them out , and you can tell right away if a wire is /has power and go from there. It is nice to know the color, but for some reason a lot of vehicles don't always agree with wire colors. There is no question when you see it with the test light.
Have a good day !