Garmin StreetPilot III, Duracell Alkaline Battery Damage To PCB, Repair Attempt - Page 1
Forum section: electronics / repair

author: SgtRock
author_rank: Unknown
timestamp: November 24, 2011, 05:04:31 am
content: Greetings EEVBees:--I am trying to repair the pictured Garmin StreetPilot III for a friend of mine. It is quite a nice unit, and well worth repairing. It even functions as a speedometer.--As you can see from the attached pictures. The ability of Duracell battery juice to eat through all manner of things is truly amazing. These cells have a durable ability to destroy things long after the charge is gone; hence the "Dura" in the name."Sir we could fix the X9D disintagrator if only we had a substance that can dissolve unobtanium." "Your in luck Sergeant Thorkild, we just happen to have a Duracell battery that has been kept in a stasis field, in order not to eat its way out of the osmium-iridium safety container"--Have a look at the last picture, g7. I only see one trace going in to the obliterated area and one coming out. I propose using a conductive pen to reconnect these traces, and to repair all the other bad ones. Judging by another ring structure on the board, I do not think any traces connected to the one in the picture. This attempted repair will not be any fun, the traces are very very fine and close together.--If the above does not work, I am not quite sure how to proceed. It seems very unlikely that I will ever find a picture of the PCB. I may buy another unit, working or not, if it is cheap, just so I can determine the correct routing.--Any and all advice and information on this problem, would be appreciated.--P.S. If any one can tell me how to get the pictures into the body of the text, rather than at the end, I would appreciate knowing. Thanks."If you build a better mousetrap, you will catch better mice."George Gobel 1919 1991Best RegardsClear Ether

author: joelby
author_rank: Frequent Contributor
timestamp: November 24, 2011, 05:06:41 am
content: Can you solder a thin wire (e.g. wire wrap wire) from the via at the top left of the broken trace to the left edge of the SMD component?

author: amspire
author_rank: Super Contributor
timestamp: November 24, 2011, 05:19:15 am
content: First you need to neutralize the battery leakage.Put some white vinegar in a jar, dilute with about the same amount of water, and brush it everywhere you see spillage.When you have cleaned it up, make a weak solution of sodium bicarb, and brush that on to neutralize the acidic vinegar, then liberally rinse everything including the board in water. If your tap water has a lot of disolved mineral content, it may be a good idea to get some rain water, demineralized or distilled water.Let everything dry out.I agree with joelby, use wire wrap wire, or wire from a cat5 cable to bypass the corroded tracks. Go back before the corrosion starts. After the wire is soldered, put a few blobs of glue along the track. Not beautiful but much more reliable then trying to use the silver paint. It is hard to do neat silver paint tracks anyway.Richard

author: Conrad Hoffman
author_rank: Super Contributor
timestamp: November 24, 2011, 05:58:53 am
content: Good advice above. It's not just Duracells, but almost any alkaline. Drippings from the Energizer Bunny will corrode things just as bad. The key is never leave alkalines in a device not in use and never ever let them discharge. I have an answering machine that's cleverly designed to use minimum current- until the batteries get weak. Then the current draw skyrockets, causing them to go completely dead and leak like crazy. GPS units tend to draw too much current for non-alkalines, so they should be run on NiMH rechargeables if possible.

author: SgtRock
author_rank: Unknown
timestamp: November 24, 2011, 06:10:15 am
content: Dear Joelby & Richard:--Thanks for the good advice. I will take it.--Joelby. I believe I understand you. And I believe I agree. But, just to make sure I understand; you want me to solder a wire from the truncated trace at the top of picture g7, to the black SMD chip which is to the right and below (seen in picture g6) at about a 45 degree angle, yes?--In the remaining cases should I solder from via to via if possible or should I attempt to solder on to the remaining good parts of the traces.--I cannot thank you enough for your good advice. Let me know if you would like to see more and better pictures in any area of board."Get ready, little lady. Hell is coming to breakfast."Chief Dan George 1899 1981Best RegardsClear Ether

author: joelby
author_rank: Frequent Contributor
timestamp: November 24, 2011, 06:16:46 am
content: Is there more than one damaged trace? (I only had a quick look at your high resolution image before they were replaced)Solder to vias if possible, as this will be much easier. Soldering to the side of SMT components will be fine if the exposed edge is large enough and your wire is fine enough. Glue will help to sure up the connection.As a last resort, carefully scrape away the solder mask and solder to the trace. You should only have to do this if a trace disappears under a large component and you can't figure out where it goes.

author: metalphreak
author_rank: Frequent Contributor
timestamp: November 24, 2011, 12:25:44 pm
content: These might be helpful: