Zumo 665LM power cable

[Mudslide Miller]

So recently I've had intermittent power to my Zumo 665LM. Lately it's been running off of the internal battery and then goes dead after discharging. The hard line power cable that the GPS snaps on to has 18 pins that make contact with the back of the Zumo. Does anyone know what pins the power comes to and what the voltage should be? I'm not reading anything to the mount pins.

I called Garmin and unbelievably they tell me there is no schematic available to tell me which pins should have power. They, of course, just want me to buy a new power cable but I want to make sure it's not a connection problem first. But won't know until I know which pins the power should be coming to. Thanks for any help.

EDIT: In doing some more reading online it looks like it should have 5 volts incoming. Still just need to know to which of the 18 pins. If someone wouldn't mind metering theirs and telling me which ones, I would greatly appreciate it.

 

[Fred W]

I do not know the direct answer to your question on pin-out, but have dealt with similar issues in the past with several other Garmin / cradle models. A GPS cradle mounted on the dash or handlebars of a motorcycle is a particularly harsh environment for electrical pressure contacts.

The ultimate fix has typically been just to clean the contacts, on both sides, thoroughly, but not abrasively. The pins are typically gold plated, for weather resistance, and also for maximum conductivity (this is a very good thing). My extensive experience with gold plated electrical contacts in the industry is that they will still oxidize when exposed to the right (worst) ambient conditions, though certainly not as quickly as most other metals, And also that the gold contact plating is very thin (for obvious financial reasons) so anything particularly abrasive is to be avoided to maintain longevity.

The "old standard" was to use a #2 pencil eraser to try and de-oxidize and clean these contact surfaces, as those typically are only slightly abrasive, though not excessively, and used to be omnipresent. I've used spray contact cleaner and q-tip swabs to varying degrees of success, depending on how corroded the contact surface is. And that is probably a good "preventive" maintenance once you've been bitten. But it usually takes the pencil eraser to get things back to square one once the damage is done.

I wish that our forum friend ionbeam were still participating here as I know he would have some valuable input on this, as his direct and hands on experience in the field surpasses even my own. I know that he monitors still occasionally. Maybe he will be willing to weigh in?

 

[SouthernCruizer]

I just checked (2) Garmin 665 cradles that are mounted on my Versys and Wee Strom...neither of them have single pins that return test values above a few hundred mV...I don't know what this means....is it possible that the power comes from a combination of 2 or more pins?? Some pins show zero voltage.

Sorry I couldn't deliver the solution.

 

[RossKean]

GOOGLE!!

https://www.ukgser.com/forums/showthread.php/446607-Zumo-660-cradle-wiring-on-pins

 

[SouthernCruizer]

I used that schematic to check voltage across pins 17 & 18, still only getting mV readings, yet the mount works perfectly.

I suggest a good cleaning with contact cleaner and possibly WD 40 or other lube...

 

[RossKean]

Do pins have to be depressed to get a reading? Maybe all (or at least V and Gnd) have to be pressed.

\The link includes some information on disassembly. Seems to me that I put a SMALL amount of dielectric grease on a cloth and wiped the pins as well as exercising them in and out a few times to clean and lubricate pins. I have seen some mounts that were pretty crusted up and with immobile pins due to corrosion. I try my best to keep the mount dry and make sure I use the cover when the GPS is off the bike.

 

[Mudslide Miller]

Thanks for the input guys. And thanks for the diagram Ross; exactly what I was looking for. I’ll check this out in the next couple of days. Cleaning the contacts was the first thing I did Fred as I suspected the same thing, but no love. Corrosion is not as much an issue here in Phx as it would be in other moist areas of the country.

 

[dcarver]