2005 PowerBook G4 Special Report: Erratic Trackpad behavior

Erratic Trackpad behavior

Apple's 2005 PowerBook G4 models are the first with new trackpads manufactured by Cypress Semiconductor, not Synaptics. Unfortunately, the new trackpads appear not only to be generally slower in scrolling, but in some cases exhibit erratic behavior.

Problems include taps and clicks not being recognized, jumpy cursor movement and more. One model of 2005 PowerBook G4 has emerged as the most susceptible to these issues based on a number of reader reports: The 1.67 GHz PowerBook G4 17".

Taps not recognized MacFixIt reader Terry Dorn reports an issue where taps on the trackpad -- when configured to act as mouse clicks -- do not work reliably:

Dorn writes:

"Purchased a new PowerBook G4 15" (2005) from local retailer about two weeks ago, and this past weekend began to notice erratic behavior from the trackpad. Namely, taps (single or double) not always recognized, and sometimes it won't come out of sleep mode by simply tapping on the trackpad. Otherwise, I love it. Looks like a trip back to the store, which is an authorized Apple reseller and thankfully they have a good repair department."

Jumpy, inconsistent behavior MacFixIt reader Ben Markens notes that drag processes can be cut short abruptly "I have noticed erratic behavior with my new 15" 1.67 GHz G4. Click and drag seems to drop prematurely on a regular basis. No problem when using a mouse."

Alan D adds "The touchpad button on my new 15" PB is very stiff and awkward to use. Many lost drags and missed clicks."

Chris notes an apparent new tracking speed scheme that allows quicker movement horizontally than vertically:

"I've noted some differences with the trackpad on my 2005 PowerBook G4 15". For me, it appears to be a little more complicated than just being slow -- it seems to depend upon which direction I'm dragging.

"From left to right, things are pretty normal, but from top to bottom, tracking speed seems to be roughly half. I can kind of see what they're going for...the screen is wider than it is tall, so you don't need as much acceleration top to bottom. However, this can be very confusing when moving from a previous machine with a trackpad that doesn't work this way, particularly when going diagonally. I find I have to constantly reposition my finger, compared to my 12" 1GHz machine where trackpad use is basically transparent for me at this point. If this is indeed a new feature, I hope they eventually include an axis ratio option in future software revisions."

"Stuck" trackpad A number of readers report that the trackpads on 2005 PowerBook G4s take a second or two to react to new movement after being inactive for an extended period of time.

MacFixIt reader Lebn writes:

"I just replaced my 800Mhz G3 iBook with a 12" PowerBook, 2005 1.5 GHz. Reading the trackpad reports of other users I was initially glad that my trackpad seemed to be free of these problems. Lately however they have started to crop up. I have not experienced the static shocks that other users have gotten, whether on AC or not. However, sometimes when I return to the PowerBook the trackpad will take a bit to respond, five seconds or so, and in bad cases even when it does respond it will only move very slowly, or jump instead of track smoothly. This is a real pain, and an issue I never saw on the iBook. Moving my fingers back and forth rapidly seems to kind of get it "unstuck", but it may just be that it takes a while. I have seen this slow/jumpy trackpad behavior more on battery power than on AC."

Kevin Pierce adds "I find that the cursor occasionally gets stuck in addition to slow response. If I switch to another application (command-tab) and back it typically frees itself (it?s not stuck in the app I switch to)."

Static interference? Some users are attributing this issue to static interference -- a scenario for which we are seeking confirmation.

Marcello Azevedo writes:

"I'm having the same issues on my PBG4 2005's track-pad, it seems to me that the track-pad is prone to static interference, it always happens to me after I walk around and try to use the track-pad. It has been consistently erratic under this scenario."

Solutions

Knowledge Base document offering temporary fix Apple has posted a Knowledge Base document (#301047) detailing the process for "resetting" the PowerBook trackpad -- which temporarily eliminates some cases of erratic behavior on 2005 models.

The process is as follows:

"Make sure you test all parts of the trackpad surface and be sure you're using just one finger. Multiple fingers could cause erratic behavior.

"Reset the trackpad by placing your entire palm directly onto the whole trackpad for 3 to 4 seconds, and then remove your hand from the trackpad in one smooth motion."

MouseZoom Some users have reported success in working around the limitations of the new trackpad using MouseZoom, a preference pane which speeds up mouse cursor movement in Mac OS X, to improve the usability of the new trackpads.

Resetting the PMU Some readers report that resetting the PowerBook PMU resolves the trackpad inconsistencies.

One reader writes:

"Called Apple about the problem with the trackpad on my 6 day old PowerBook. They had me reset the PMU and that fixed it. Note that the PMU reset procedure has changed since my old PowerBook. Now you just unplug the AC adaptor, remove the battery, hold down the power button for 5 seconds, replace the battery, and plug in the AC adaptor, then restart."

Turn off "Ignore accidental trackpad input" A handful of readers have reported that turning off the option to "Ignore accidental trackpad input" in the "Keyboard and Mouse" pane of System Preferences results in more predictable, faster trackpad behavior.

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