Repairing Force FC-68611 Ultra COB LED Slim Light 15W

Some specs first:

• Operating time 2.5 hours,
• Charging time 3.5 hours using a MicroUSB charger,
• Power 15Watt, brightness 935 Lumen, variable intensity,
• 360° swivel base with strong magnet,
• Charging indicator,
• Foldable hook.

The LED light contains a Li-Ion battery rated 3.7 Volts, 2200 mAh. It looks similar to the item from Adafruit or here. Still need to find out if the dimensions are the same and the connector is the same. At first sight it looks like a match.

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Netlist:

GND (Red)
C1-1
C2-1
C3-1
C4-2
C5-2
J1-5
J2-1
J3-2
J3-3
TP-LED-
R05-1
U1-1
U1-3
U3-1
D2-3
R03-1
5V (Brown)
J1-1
D1-(+)
TP+
5V_2 (Lavender)
D1-(-)
R01-1
R02-1
5V_3 (Purple)
C1-2
C2-2
C3-2
D3-(+)
D4-(+)
R01-2
R02-2
R08-1
U1-4
U1-8
BAT+ (Blue)
J2-2
R09-2
R10-1
U2-2
Q2-2
R12-1
C7-1
C6-1
C4-1
C5-1
U1-5
TP-BAT+
GRAY25
U1-2
R05-2
YELLOW
R13-1
R14-1
R15-1
R16-1
R17-1
R18-1
Q2-3
GREEN
Q2-1
R12-2
C6-2
C7-2
J4-1
TP/VR
LIGHT GREEN
J4-2
R04-1
TP/VR
LED+ (Orange)
J3-1
R13-2
R14-2
R15-2
R16-2
R17-2
R18-2
TP-LED+
ChargeState1: (LightTurquois)
U1-7
R06-1
ChargeState1_2: (LightTurquois)
R06-2
D3-(-)
ChargeState2: (LightTurquois)
U1-6
R07-2
ChargeState2_2: (LightTurquois)
R07-1
D4-(-)
Turquois:
D5-(-)
R11-1
U2-3
BlueGray:
R11-2
U3-2
U2-1
LightYellow:
U3-3
R10-2
DarkRed:
D5-(+)
R09-1
Pink:
D2-1
R08-2
Gold:
D2-2
R03-2
R04-2
NC (Also Yellow ;-()
J1-2
J1-3
J1-4


There are some known issues with the LED light:
Light starts to flicker or even stops completely. At the place where the body goes from wide to small, the body is quite flexible. At this point is the connection of the wires to the led bar. Right after the soldering the wire snaps off. Strip the wire again and reattach it to the LED Strip. After that apply some hot glue to give it strength. Even if the other lead is not disconnected, strip the wire again and do the other side as well. Otherwise the other side will fail soon.

Light is not working at all anymore.
Possibly the physical switch is defective. You can try to replace the switch with another one. Bas at PreFocus contacted me if I had a part number of the switch. I could not help him at that moment so he figured out himself. He changed the switch with another one from TinyTronics (10KPOTAUDIO1CHSWITCH and KNOPBKOR). The height of the switch is not ideal, but you can shorten it with a dremel to make it fit even better. Thanks Bas for the great repair tip! The switch is now used only as an on/of switch, but it is probably als possible to control the brightness if you connect the switch completely. Photo: Bas de Theije

Charging does not work. The light does not activate after connecting the charger to the microUSB. At the location of the connector there are wires soldered to the PCB. One of the leads is not connected to the PCB anymore. Just solder it back with a fine soldering tip and you are good to go.

Schematics of the PCB are on the way soon.

COB LEDs stands for Chip On Board LEDs.

So what’s next?

The current capacity of the light is not enough for a days work. Would it be possible to increase the capacity?
Sure that would be possible. In the current design I did not find a low power protection. This means that the light keeps going even when the Li-ion cell is under it’s minimum voltage. Maybe it is there, but I did not find it (yet). More testing is needed here. Also I did not find that the temperature pin of the charge IC is used. Is this bad? Maybe not when the current is at a safe level.

It would be awesome to have a 5200 mAh Li-Ion cell working properly in a light like this one.
Some features:

• Operating time which is huge
• Overcharge shutdown
• Temperature measurement/protection of the Li-Ion cell
• Over-discharge protection
• Charging LED
• Charge completed LED
• Configurable overcharge and over-discharge voltages
• Dimmable led
• Shock proof housing
• Flexible mount magnet
• MicroUSB charging connector

To do some research on the subject, it would be nice to be able to accurately measure the mAh of the Li-Ion cell and determine it’s internal resistance. I guess another project is coming to life soon . .. U3-3
R10-2
DarkRed:
D5-(+)
R09-1
Pink:
D2-1
R08-2
Gold:
D2-2
R03-2
R04-2
NC (Also Yellow ;-()
J1-2
J1-3
J1-4