****ALERT!!**** Garmin III/III Plus battery door problem

[+Team Magster]

Warning: The following procedure should not be attemted by anyone who is not deft with small hand tools as permanent damage may result.

 

This may be useful to some folks who've owned a Garmin III or III Plus for a few years.

I began having a problem with my III+ intermittently refusing to start as if batts were stone dead. Eventually the unit refused to start at all. I found information on the web (see: http://joe.mehaffey.com/spacer.htm) suggesting that that over time - especially if the unit has been dropped a few times (mine was) the battery contact springs may lose their tension and fail to make a good contact. The FAQ even suggested that Garmin has a spring wafer they'll mail you to fix this "problem".

 

I tried playing with the springs by slightly extending them. It looked to me like they were making good contact but the unit still refused to turn on. I have an electronics repair background so, failing to resolve the problem by slightly extending the springs, on a whim I shorted across the batteries with the battery door open and tried to turn the unit on. Voila! SUCCESS!!! This pointed to the battery door as the problem.

 

I took the unit to my workbench and pulled out my multimeter. Measuring resistance across the + and - battery posts on the door should measure zero resistance or zero ohms. In fact I was measuring an open or a swinging (telephone jargon for changing readings) high resistance short!

 

Looking at the positive terminal where the negative coil spring wire winds around the post seemed to be the likely culprit. I gently removed the spring wire from the post with a needle nose. Once removed I was able to tighten the "noose" a little using the same needle nose. I also noticed what appeared to be a small amount of corrosion in the groove of the positive terminal; this might be expected on battery posts over time - the same as one sees on their car battery. I used some WD-40 to spray/wipe it clean.

 

I carefully re-attached the coil spring to the post and again measured resistance: solid short/0 ohms - perfect!. I placed a fresh set of batts in the unit and it now works like new!!

 

Lessons learned:

 

1) The connection between the positive battery post and the negative coil spring is pressure fitted - it's not a soldered contact so it's susceptible to eventual corrosion or loosening over time as was mine.

 

2) When I was a repair switchman for Ma Bell our motto was "look for the obvious." This is a pretty obvious problem waiting to happen once you understand the makeup of the posts on the battery door. I'd predict a lot of older III/III+ units beginning to have this problem; mine is over two years old with lots of use.

 

3) Garmin's support sucks! I tried to call (an hour wait on hold according to the VRU) so I sent an RMA request via their web site; I intended to pay them their $125 refurb fee. That was over a week ago and I haven't heard from them. Note that the web site says to allow 5 - 7 business days for them to respond. That, in my humble opinion, is outrageous in this day and age!

 

4) Garmin stands to mine lots of dough at $125 a crack to fix this relatively minor problem.

 

Regards