mid 2010 MBP- trackpad going nuts

[Beachguy]

The MBP is 8GB and runs Sierra, current version, and is an i5. 15.4" model.

The trackpad seems to be having serious mental issues. If I try to move the pointer it either barely moves or jerks all over, and clicking doesn't always work where the pointer seems to be. (For example, I can click the Safari icon and it will open Finder instead.

With a mouse attached, it still is jerky but it is usable. I have no idea how to troubleshoot this or what may be wrong. There is no visible damage to it. Could it be a matter of just needing to clean the surface with a moist and soapy (alcohol?) towelette? I've tried resetting PRAM and I even upgraded the OS from El Capitan to see if something got hosed at the OS level. No good.

Ideas?

 

[Audit13]

Disconnect the trackpad cable and see if the mouse is still jumpy.

 

[snipecaik]

I've had some experience with the internals of similar era MacBooks, it sounds like the issue might be static discharge occurring where the trackpad connects to the motherboard. Without too much expertise you could unscrew the bottom lid (according to fixit they even use Philip head screws). From there locate the trackpad connector, disconnect and reconnect. I would also recommend covering the connector with kapton tape to prevent It from happening again.

 

[Fishrrman]

OP:

Important question:
When you're getting the jerky motion, is the laptop charger plugged into it?

If the answer to the above is "yes", try lifting the front edge of the computer as you manipulate the trackpad. Does this change things?

My old 2010 MBPro has this kind of behavior. I'm wondering if having the charger plugged in doesn't cause the battery to "swell" a very small amount, thus pressing against the bottom of the trackpad and interfering with its operation.

The trackpad works fine -- when the charger is unplugged.

 

[brdeveloper]

Stop using counterfeit chargers. This is the cause. I had the same problem on my Late-2009 White Macbook... ended up fixing the original charger to get my trackpad working properly.

 

[polbit]

I was going to mention battery as well. When it starts going bad and starts swelling up, especially when working hard, it will do that.

 

[MultiFinder17]

I had the same issue with my MacBook Air; turns out that the trackpad itself was dying. $25 on eBay for a new trackpad, 10 minutes to install it, and the MacBook is working perfectly fine again

 

[Beachguy]

The charger is indeed real Apple. I found how to turn it off in the control panel so that it didn't interfere with the mouse. Then the Mac stopped working shortly after. No battery swelling, and, oddly, the original battery.

Now, when I start it, the progress bar gets to about 40-45% and it shuts down. Tried to reset SMC and PRAM, disk check, etc. The disk test has something it wants to update but hangs. The machine does NOT shut down like it does when booting.

 

[Audit13]

Try disconnecting the battery, connect the charger, wait a few minutes to see if the Macbook powers itself on.

 

[Beachguy]

Try disconnecting the battery, connect the charger, wait a few minutes to see if the Macbook powers itself on.

It powers on it just craps out on the way to finish booting. If I go into the diagnostics screen, it stays up and running. I am wondering if the drive is going bad, perhaps.
[doublepost=1506257486][/doublepost]Oh- I was unclear that I will give the suggestion a try.

 

[Beachguy]

Reinstalling Sierra worked to get it back to running okay, other than the psychotic trackpad.