1992 Honda A/C on off problem

My 1992 Honda prelude has great AC, when it works. Sometimes for no
apparent reason, the green light under the AC button goes off and the blower
continues to blow the outside air in without cooling it first. Sometimes I
can push the button in repeatedly and it will come back on.
I thought it might be the switch until I noticed that the rear defroster has
the same problem of coming on and off. They seem to both work or not work
at the same time.

Thanks for your input,

Wesley

 

It's hard to guess as to the exact problem. It may be what is known as a
"short" which simply means that it works great when the short is not in
effect and works poorly or not at all when the short problem kicks in. If
it is a short, it's a hard problem to fix since the short problem never
seems to kick in when a mechanic tests the system. I suggest that you take
it to a Honda Dealership and have them give you an estimate on how much it
would cost to fix the problem. You may want to consider trading your 92
Honda in on a newer used Honda prelude or civic instead of paying lots of
money to have the air conditioner problem fixed.
If you want posters to explain what a "short" is--make a new post and label it:
What's a "Short". Hopefully, someone can explain better than I could explain it.

 

I must say, what sort of advice is that, "trade in the car"?

Firstly, it may be as simple as a relay or connection that's bad. When
they do work, they seem to work great. And when they don't, they
don't. That usually points to something pretty simple. I would bet
there is a common relay or wire that they both share that is bad.

Also, why run right off to a (expensive) Honda dealer? A little
troubleshooting is in order here first, and possibly a visit to
someone who specializes in auto electrics/air conditioning. Maybe a
litle research in the groups as well.

I don't turn on the blowtorch very often, but for someone who doesn't
even know what a "short" is (which is probably not the case here-
shorts usually result in blown fuses, burnt wires, or relays), you
have a lot of half-baked advice.

This is what's called an "intermittent". Current is not always getting
to your defroster switch and A/C switch. Let's not run off and trade
the car, now.

 

take a peek in the sight glass and see if there is foam in the stream.
may just need a boost in the refrig. bob