For those of you that own a Nuvi 350 with a on/off power switch problem....don't worry you're not alone.
Two days after I purchased my Nuvi 350, my switch broke too. The problem I faced was that I bought it from a so-called "Authorized Dealer" on eBay. Turns out that Garmin never heard of the dealer and therefore refused to register my Nuvi and honor the warranty. Garmin told me that my Nuvi was already registred to someone else. They did however offer to fix it for a flat $170.00 fee.
So what do you do in this type of situation? I did some research on the web and discovered that this is a common problem with the Nuvi 350.
Here's why it happens:
The on/off switch is a surface mount switch that is mounted vertically off of the main PC board.
The problem is, that there is no support behind the switch, so when you press down on the button, the very small solder leads of the switch are stressed and eventually the switch breaks off the main PC board. This is a design flaw and it could have been easily prevented by gluing a small piece of custom-fit plastic between the rear of the switch and the SD card housing to give the switch support. Also, the solder pads for the mechanical connections of the switch could have been made bigger, allowing for more surface area and more solder application.
Another possibility of failure because of poor support, is that the switch body may have bent down and away from the case's on/off flap that pushes the switch. There is a plastic stop pin in the case that prevents the flap from going down too far. So, if the switch has been bent down as much as 1/16", the flap will never reach the button on the switch.
Can it be fixed? Yes but it's not just a simple matter of just resoldering the switch. Without fixing the original support issue, the problem will certainly happen again. In some cases, the printed circuit board tracks may have lifted up off the board and need to be bypassed with wires.
The proper way to fix this problem is to improve the mechanical mounting of the switch by securing its metal body to the motherboard groundplane with pre-tinned buswire. The mechanical leads of the switch are not enough to secure the switch to the board. A custom-fit plastic block needs to be glued between the rear body of the switch and the SD card housing. Bottom line, if the switch can't move, the leads won't be stressed causing them to break.
It's very unlikely that the switch itself is bad. The life cycle of this switch is 250,000 cycles. For example, if you pressed it 20 times per day for an entire year, that would add up to 7,300 presses per year. Divide 250,000 cycles by 7,300 and it would take 34.25 years before the switch would fail. No doubt the switch will outlive the Nuvi itself.
Taking the Nuvi apart itself requires the right tools. The internal flex cables for the antenna, touch screen and LCD screen are delicate and can be torn easily if you're not careful. The antenna flex cable runs through the swivel antena shaft and is very delicate.
You will need a surface mount desoldering/soldering station with illuminated magnifier. A standard soldering iron is far too big to solder the leads and will overheat the solder pads, lifting them off the board. All work should also be performed with proper grounding to eliminate static charge issues.
To determine if your switch is broken with no other issues, please
confirm the following:
1. Pressing the on/off switch has no effect and the switch feels mushy
when pressed - no soft click.
2. The unit powers up and operates normally when using the car adapter
or USB adapter and can be turned off by pressing the reset button.
If the above conditions appear to be the symptoms of your Nuvi 350,
then most likely, the on/off switch has broken off from the main
printed circuit board.
Please contact me at KS3R at sharc dot net if you would like further information about this problem.
Amateur Radio Operator