electronic navigator in 1987 lebaron displays time only

anybody ever run into a navigator unit that appears to be hooked up ok
but I get no response from any of the 12 keys. the clock will display
the time but cannot be adjusted. no other functions appear. its like
the whole system is locked. is there any super-reset that works for
these? it has a bunch of cool funtions I'd love to access. If it
matters, pressing the mileage trip and trip reset on the electronic
speedometer also have no effect. All the guages and speedometer work
fine, as does the electronic voice unit.

any input you can give would be appreciated.

 

I owned a 1987 LeBaron GTS that had that "trip computer" option. The keys
used a rubber membrane keypad type switch underneath that made contact with
the copper circuit paths. They had a tendency to get gummed up and the
conductive material attached to the rubber membrane just plain wore away.

My unit lasted about 6 years before I had problems with the keys I used to
use all the time (miles driven, MPG, elapsed time, etc. I was able to open
the front and remove and clean the pads with electrical contact cleaner. I
then used conductive epoxy to recoat the pads. This fix lasted the
remaining 3.5 years that I owned the vehicle.

My guess is you have the same situation. Remove the unit, open it
carefully, then take a look at the contacts for the buttons. If you have a
12VDC power supply, you can "simulate depressing buttons by shorting out
across the paths on the circuit board using anything conductive. If this
works, then you will know what the problem is and how you may be able to fix
it. Good luck

Bob

 

thanks, I'll give it a shot. I, too, have the 1987 GTS, its a great
car.

 

I loved that car ...

 

that seems to be the problem. Did you need a soldering iron to get
those switches off?

 

No soldering involved as I recall.

It has been about 12 years, but if memory serves me correctly, I was able to
open everything up with a simple screwdriver once I had the entire unit out
and on my work bench. Be careful though when you open the front panel as I
also seem to recall there were some small plastic parts associated with the
buttons that you do not want to lose. This was not a difficult job. If you
do not have any chemical electrical contact cleaner, then you can wipe down
the PCB conductor paths with a soft rag to get as much junk off as possible,
then use a pink pencil type eraser to clean them up from there to get them
shiny again.

The only caution here is with the rubber membrane conductor that is screen
printed on the rubber. Try to see if just cleaning the copper contacts works
first before doing anything there as this wears off very easily. Since mine
were shot, I cleaned with 100% isopropyl alcohol and then painted each
section with the conductive epoxy. I used stuff made for fixing rear window
defoggers available at the auto parts store. You may find something that
works better. I was always worried it would come off and stop working, but
I was lucky and it seemed to hold up well for the remaining years I owned
the vehicle.

Good luck and post your results.

Bob

 

You're a genius, Bob, that worked perfectly. All the features of the
navigator are up and running. I pulled off the cover for the
speedo-guage cover to see if the non-functioning switches for the trip
and trip reset were of the same style. They were, and after trying
your solution, they are working great. Thanks so much, its great to
have all that stuff working.

 

Glad I could help. Thanks for letting me know it worked.

I have gotten so much great help from the people in this newsgroup over the
last 10 or more years ... it is nice to return a favor now and again.

Bob