[V8] Cruise control under control

[Mike LaRosa]

nice job :)

Mike LaRosa


--- m35a1 at juno.com wrote:

> Well, I got it working. 
> Got a tip from Tony that the control unit in the
> engine compartment is
> actually an electric vacuum pump. Don't understand
> why they just didn't
> use engine vacuum, but gotta deal with it.
> Tried to get it to run---no luck. No power at the
> connector plug. Took it
> off the car and onto the bench.
> I took the top off the housing of the control unit
> and studied the
> wiring; wired it direct and it worked, so that was
> not the problem. 
> Went under the dash and starting checking power at
> all the wiring. Could
> not get power to the plug for the control unit at
> all. Then read the
> owner's manual which says that the cruise only works
> when the car is in
> drive going at least 22 mph. Well, that would be
> kinda hard to do,
> sitting in the driveway. 
> Then I checked the wiring at the switch on the brake
> pedal. There was no
> continuity across the switch, meaning that the
> switch was open. I thought
> that would be normal, as a brake light switch is
> normally open, and
> closes when the pedal is depressed. But it did not
> close when the pedal
> was depressed. Something's amiss here. I checked the
> vacuum portion of
> the switch. With the pedal at rest, the vacuum
> switch vented to
> atmosphere, same when the pedal was depressed. Logic
> says that something
> should change when the pedal is depressed. So I took
> the switch off. It's
> function is that the electric switch is normally
> closed and opens when
> the pedal is depressed, and the vacuum is normally
> closed and opens when
> the pedal is depressed. 
> I discovered that the switch was not screwed in far
> enough for it to stay
> closed at rest and open when the pedal was
> depressed. I tried screwing it
> in further but it kept popping back out.
> Turns out the the plastic grommet that the switch is
> screwed into had
> broken and it would not hold the switch in place
> properly. I found a
> large nut to fit the threads on the switch in my
> pile of goodies. I
> replaced the switch into the grommet then screwed
> the large nut onto the
> switch behind the plastic grommet so now the switch
> can be held in the
> proper position.
> Now the cruise is working again.
> That explains why folks don't usually get stuff like
> this fixed when it
> breaks. I spent 6 hours diagnosing, researching,
> repairing and testing.
> With shop rates in the $150/hr. range, that's $900
> to get the cruise
> working again.
> Not like I'd pay that kinda money!
> Thanx
> Ken
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