hand controller keys not responding

[bigZ]

My CGEM's hand controller's buttons sometimes don't respond to pressing.  I've taken apart the hand controller and cleaned all the contacts but still no help.  Is the motor board's battery have anything to do with this problem?  By the way, I replaced the motor board less than a year ago. The battery must've been a fairly new one, right?

[Steve Ward]

Did you clean the back of the rubber keypad buttons as well ... ?

[Cosmic Geoff]

I have had this problem with Celestron hand controllers and found that dismantling and cleaning the contacts and rubbers effects at least a partial cure. No battery involved.

[bigZ]

I wonder if the coiled cord connections between the hand controller and the hand controller port are flakey?

[bigZ]

On 15/04/2024 at 09:23, Steve Ward said:

Did you clean the back of the rubber keypad buttons as well ... ?

Thank you for your reply.  Yes.  I used rubbing alcohol.  If I do that cleaning again, I'll use denatured alcohol or acetone sparingly with Q-tips.  OR, I'll also try operating the mount using NexRemote.  I wonder if NexRemote bypasses the hand controller?

[Cosmic Geoff]

Are all the buttons failing to respond, or just some of them? or do they only work if you press hard? It should be possible to distinguish between a button contact or other electronic problem.

If it's a button problem, you should be able to work around it with NexRemote. Or just buy another controller. (Some people have deep pockets).

[Carbon Brush]

Adding to the good advice from @Cosmic Geoff.

The rubber buttons are made with a conductive layer to bridge the PCB tracks below.
The conductive area can become worn. Not all buttons fail together and a harder press can make them work. Hence Geoff's questions.
If it looks like the conductive layer has failed, you can prove, and make a temporary repair,  by rubbing a soft pencil on the button pad.
Maybe a careful brush from a PCB repair pen (silver loaded conductive paint) might help. I have never tried it on a flexible keyboard application but it does work on PCB tracks.

For cleaning I would use Isopropanol intended for electronics cleaning. This is 99% and more pure.
The 'over the counter' cleaning agents often contain additives that can mask problems.
For example, denatured alcohol (called methylated spirits over here) is in majority ethanol + methanol.
However, to stop you being (very unwisely) tempted to drink the stuff, there are dye additives. These can leave deposits.

HTH, David.