OK, so I have an 88 convertable. I put the top down yesterday. After the sun dropped I went and put the top up. Later that night I pull into the shop & try and drop the top again. This time I get the warning beep and hear the motor start. But only in the mode for putting the top up. If I twist the switch for putting it down I get nothing. No beeping or anything. I did pull the switch and did bolth an ohm test and a true voltage test. Bolth of the tests came back as good. So the switch is working & has voltage.
Thank you in advance.

 

Update, I left the switchs unhooked lastnight. I pull in the shop today hook it up and it works like a champ I know that it cant be trusted. So where should I start the search?

 

I have had the EXACT same problem. '88 'vert and my top will always go up, but sometimes won't go down. Usually I wiggle the switch, rev the engine, move the shifter around until it works, but this whole week it has not gone down at all. No beeping, nothing. Everything works fine going up. One thing I noticed is that SOMETIMES when I turn the switch to put it down, I can hear something click behind me (I assume it's the top motor), but it still doesn't go down, so that makes me think that even if the switch is working the motor or something might be crapping out. I am going to put the motors in "neutral" as someone suggested so I can put it up and down by hand until I figure out the problem. One of these weekends I will tear it all apart and investigate. We should keep each other posted if we make any progress.

 

I've had similar issues with mine. Check to make sure you have a good connection on your emergency brake switch, among other things, before you go the 'complete teardown' route.

 

Yep, parking brake switch is the most common issue if it is not going down

 

Wouldn't the parking brake switch cause it to not go up as well? I've never had a single problem putting it back up.

 

Well, my e-brake switch appears to be working fine, so I'm moving my trouble shooting back to the electric top motors.

 

Take a look at the switch. That was my problem.