Without seeing the picture I will speculate a bit on the soldering points.
There are pictures at the end of this post.
-------"The Green Light of Death"--------
Better known as power light on but the screen is dead
Tomtom symptoms typical of a damaged charging regulator/zener diode
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1. When you plug in the Tomtom, the green power light comes on but Tomtom fails to start (no screen activity) and the Tomtom fails to charge
2. If you replace the battery with a charged battery the Tomtom works but does not charge the battery when plugged in. When the battery runs out the Tomtom will not start when plugged in, the green power light is on.
3. Maybe you smelled electrical smoke when the zener diode burned?
Possible reasons for blown regulator/zener diode
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1. Defective car charger supplying too much voltage to Tomtom.
2. Sometimes electrical components just go bad.
The fix - Modification to repair a broken Tomtom having symptoms of "Green light of death"
Steps are documented with pictures at the end of this post
Please note that the fix on this page is to solder one wire to the circuit board and eliminate the battery! by drawing 5vDC from the burned up diode position and supply the 5vDC to the red wire battery molex plug wire. This is not the best way but works.
The better way to repair this is the next post where we install a tiny Li-on regulated battery charging board that fits into the case of a TT which allows us to keep the battery.
It is still a good idea to read this post for information
Background information
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D5(for Tomtom model One Version2) and D8(for Tomtom models Go630-Go930) are locations on the TomTom circuit board for zener diodes. If the zener diode at that location gets damaged then the Tomtom will not power on, only the green LED will light up when the Tomtom is pugged in.
The D5 and D8 locations are very near the mini-USB plug on the printed circuit board. If the zener diode has burned then the markings on the Tomtom circuit board may be gone. It is very easy to tell if the zener diode burned up just by looking at it. You should remove the damaged zener diode from the circuit board prior to soldering the jumper wire. It is ok to just remove the plastic and leave the metal stubs of the zener diode, just make sure you do not bridge the stubs together with solder when attaching the jumper wire.
This is where the jumper wire is attached
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On the TT One-V2 the location to attach the jumper wire is labeled D5. It will be the lower of the two pads (inside the rectangle) facing down toward the bottom of the Tomtom One-V2. There is +5v DC present on the lower D5 pad when the Tomtom is plugged in, we will attach a jumper wire to that pad in order to supply power to the Tomtom.
On the Go630 - Go930 models the location to attach the jumper wire is labeled D8. It will be the upper of the two pads (inside the rectangle) facing up toward the top of the Tomtom Go630 - Go930. There is +5v DC present on the upper D8 pad when the Tomtom is plugged in, we will attach a jumper wire to that pad in order to supply power to the Tomtom.
Google search D8 tomtom or D5 tomtom and you will find pics of this diode and where it is located on the Tomtom circuit board. It will help verify the location if there are no markings on your Tomtom circuit board.
You can verify the correct spot for the jumper wire with a multimeter, when the Tomtom is plugged in there will be +5vDC on the correct pad. The other pad will have no voltage.
This modification requires some soldering. It adds a jumper wire from either D5 or D8 cathode (+5v DC) pad to the positive battery input on the TT using the existing red wire and existing molex plug from the battery (see pics below). This will supply continuous +5v voltage to the TT when plugged in and the TT will function. One bad side effect is the battery is removed and replaced by the jumper wire. The TT will only have power when plugged in but that is better than broken.
Warning! You should not leave the battery connected after doing this mod because it will damage the battery and make a fire hazard, charging the 3.7v lithium batteries using more than 4.2v is asking for trouble! This mod should not be used to charge the battery because 5vDC will overcharge the battery . Look farther down in this post for an inexpensive repair method that both powers the Tomtom and charges the battery using a regulated power supply from ebay. The power supply looks (to me) small enough to mount inside the TT case. There are many choices if you do the ebay search.
The battery has 3 wires, red(+) , black( -) , yellow(T) (middle yellow wire is thermistor temp sensor, not used for charging)
You wonder what the temp sensor does?
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It is a safety feature for the charging system and battery. If the temp gets too high in the battery it could catch on fire or explode! That could happen if you leave the modified TT battery plugged in after connecting the +5v DC
Some would ask why not just replace the diode? (I tried this)
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That would not repair the defective charging regulator and did not work. From what I understand the charging regulator is the main problem, the diode gets damaged after the charging regulator malfunctions.(maybe)
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So now you wonder if maybe there is a better way to do a repair for this issue that does not involve replacing the diode and regulator?
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Yes, there are now tiny Li-on regulated battery charging boards that can fit into the case of a TT. You would only need to supply the voltage (usually 4.5v - 5.5v DC) to the board from jumping a wire from D5 or D8 cathode +5v DC pad to positive + input side of charging board and supply the ground from somewhere on TT. Then run wires to splice into TT battery red + and black - and you have a safe battery charger that is a regulated power supply that senses charge state and stops charging when battery is charged. The charging / charged battery would power the Tomtom. Update 12-28-14: I have ordered a few of these chargers and am waiting for them to arrive. The repairs will be documented and posted to this thread.
I supply an example of a regulated charger found on ebay that may be suitable (and price is cheap!). To make it fit into the TT case you would have to remove the mini-USB receptacle on the charger, but that is not difficult. Note that it has Led lights to indicate charging or fully charged. It will discontinue charging once the battery reached full charge. To see the repair using this method please see the next post.
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ebay search TP4056 charger Module
TP4056 charger Module
1.Charge module- Linear charging.
2. Current- 1A adjustable.
3. Input voltage- 4.5V-5.5V
4.Full charge voltage- 4.2V.
A. Led indicator- red is charging blue is full charged.
B. Input interface- Mini USB.
C. Work temperature- -10 to +85.
D. Inversed polarity- NO.
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And finally, here are the pictures of the modification to repair a broken Tomtom having symptoms of "Green light of death"
On the TT-One V2, solder a jumper wire to the lower pad of the D5 rectangle. D5 may be silkscreened on the PCB, it is simply the location on the board where the zener diode is/was mounted. The red wire was scavenged from an old USB cable. The dark area around the soldered area is flux. The old burned charred diode was removed from the board, then the area was cleaned with acetone prior to soldering. Make sure you do not bridge the two pads (upper and lower) in the D5 rectangle together when you solder, you can check that with a multimeter if you are uncertain.
After cleaning with acetone you can actually see the board again. Applied clear fingernail polish to the soldered area and the exposed wire to seal the repair. You can now see the silkscreened rectangle on the PCB where the burned zener diode was removed. The wire is soldered to the lower pad in the silkscreened rectangle (remember this is Tomtom One-V2, on the Tomtom Go630 - Go930 models it is different). This pad supplies +5vDC when the TomTom is plugged in.
Battery molex plug from a Tomtom battery, this will be connected to the wire that is soldered to D5 pad.
The molex plug connected to the wire from D5 diode pad and plugged into the Tomtom battery connector where battery goes, no more battery with this mod.The black and yellow wires are no longer needed, black was ground and yellow was thermistor
The Tomtom is plugged into USB power supply and the Tomtom now works, the "green light of death" has been repaired. This repair method should be ok for any Tomtom as long as you can find the +5vDC
Disclaimer! I take no responsibility if you burn yourself or further damage your Tomtom using these instructions. These instructions should be considered as a general guide to point you in the right direction, it is your responsibility to properly prepare prior to performing any electrical repair. It is your responsibility to use safe practices and common sense!
Attached my notes on this problem, maybe can help someone - has diode info, etc.
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