Second-gen Bandit gauge LED swap

Let's face it. While the second generation Bandit's gauges are fairly well designed and functional, they're bland. Plain yellow-orange is simply dull. After reading up on the project at Maximum-Suzuki, I decided to make a mid-winter project of adding some excitement to my "cluster". It took about five hours, but I was watching my two small kids and being extremely cautious. You could probably do it in two.

First, a caveat: This project is not for the impatient, the ham-handed, or the poor of vision. It takes some time and is a strain on both the eyes and the back. Delicate, precision work is required, and you must have good tool skills.

Materials and tools required:

LEDs - Depending on your color preferences, up to ten LEDs are required. If you're reusing the six orange ones, that number will be less. Keep in mind that accidents happen and that faulty compoenents occur. Have a few extra. See below for sourcing.

Resistors - You'll need two 470 ohm resisitors to add the four LEDs not present from the factory. These can be found at Digikey or your local Radio Shack. I used the 1/4 watt variety, but the smaller 1/8 watt ones may work as well. Consult an expert if you go small.

Soldering iron - You'll need a clean, fine point for this project. I used my old, crusty iron, but I used a Dremel and a file to create a good point and to freshen it as it dulled and became sooty. Heat transfer depends on good metal contact.

Desoldering braid - Also available at Radio Shack, you'll only need a foot or so. This was the first time I've used it. It's not rocket surgery. Simply place it on the solder to be removed and press on the end of it with your iron.

#1 and #2 Phillips screwdrivers - Use clean, sharp tools to avoid damage to fasteners and other components.

Tweezers or light-pressure surgical clamp - Tweezers work fine, but a clamp can make things easier. Be aware that heat from soldering may soften the LEDs and allow them to be squished by a clamp.

Finding which LEDs to use was a chore. I narrowed it down to the following items:

Blue: http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=475-1007-1-ND
Red: http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=475-1133-1-ND

Ultimately, I ended up buying on ebay. The auction link won't be around long, so here's some of the description. The seller is oznium925. I paid about $20 for (10) ea. red and blue.

PLCC stands for Plastic Leaded Chip Carrier. The PLCC-2 size LEDs are commonly used in car dashboard and gauge cluster illumination. To change the color of your dash lights, you can use these LEDs. First figure out what size LEDs are in your dash. Some cars have a typical bulb, while others use a surface mount LED soldered directly to the circuit board.

Specifications for PLCC2 Surface mount Top Led

Size: 3.5 x 2.8mm Viewing Angle: 120 degrees Current: 20 mA

Color	MCD (Min.)	MCD (Typ.)	Voltage (Min.)	Voltage (Typ.)	Wavelength
Blue	130	200	3.0	3.2	472
Red	310	460	1.6	1.9	630
Green	350	520	3.0	3.2	519
White	650	850	3.0	3.2	x=0.30 y=0.32
Orange	130	190	1.8	2.0	603
Yellow	220	330	1.8	2.0	587
Pink	170	250	3.0	3.2	x=0.5 y=0.23

Let's begin!

First, you'll need to get the gauge cluster out. This involves pulling the windshield and front fairings. Be sure you understand how to do this without breaking tabs of the various parts. You'll remove the four nuts holding the headlight housing, then the two holding the cluster. Using the release tabs, unplug both wire bundles and the cluster is free.

Find a clean, soft, well-lit workspace. You don't want to scratch up the "chrome" finish on your gauges, and the needles and electronic components are fragile. I like to lay an old bath towel on my worktop.

This image shows the screws holding the assembly together. Remove two screws securing the upper housing half (#1). This is an S model cluster, and the naked version varies slightly. Next, remove the seven screws securing the front bezel to the white housing (#2). Pull it off and set it aside. There are four screws recessed into the white housing (#3). These hold the circuit board in place. There are also two on the circuit board itself, so go ahead and pull these four now. Finally, pull the black plug securing the wire bundle at the rear of the housing (#4).

The second image shows the front of the assembly. The five clear LEDs are the oil pressure, neutral, high-beam, and signal indicators. The two small buttons near the bottom are the clock and odometer switches. Any of these could be replaced at this time if defective.

Remove the two remaining screws securing the circuit board to the housing (#5). All screws to this point call for a #2 Phillips. Use a new, clean screwdriver to avoid slippage. You do not want to strip screwheads or damage the circuit board. Use firm pressure and keep the screwdriver perfectly aligned with the screw shank.

At this point, I wrapped a folded paper towel around one gauge face and secured it with a rubber band to protect the needle and the black finish. Always be aware of the needles, and take extreme care to not swing them outside their normal range or press on them.

This image shows the fourteen points that you'll need to desolder to remove the gauge face and needle actuator, giving you access to the LEDs. Ten pins from the digital display (#6) should be desoldered first. Press the heated iron down onto the braid, with the end of the braid up against the pin and lying on the solder joint. You may need to approach from both sides, but move around the row to keep from getting too much heat in one area.

Once all ten pins are loose to the touch, move on to the four securing the needle actuator (#7). They're much easier. Apparently I didn't label anything #8, so let's move on to #9, which are four tabs securing the actuator to the circuit board. Genty pry them open so they won't snag when we lift the parts off the board. Finally, Remove the two aluminum screws securing the gauge face to the board. Use a fresh #1 Phillips for these, pressing firmly and in line with the screw shanks. Suppor the gauge face carefully, and don't apply any pressure to the needles.

Once you've removed the gauge faces and needle actuators, you'll have an open view of the circuit board. This image shows the locations of the three stock LEDs (#11), the two we'll add (#12), and the resistor required to complete the circuit for them.

For each LED you wish to remove, press the braid against one end and remove the bulk of the solder. Repeat on the other end. Now, grasp the LED with your tweezers and apply heat to one end. It should lift from the circuit board slightly. Now, apply heat at the other end to free it completely.

Now, inspect the solder left behind. Ideally, you want a small, smooth mound on at least one contact point. If there's too much, us the braid to remove some. If both points are free of solder, add a small amount to one point.

LEDs, being diodes, only allow current flow in one direction. Each has a corner marked with a small triangle-shaped depression, indicating the cathode. This must be oriented to match the cathode markings on the circuit board. This image shows these cathode indicators.

If you plan on reusing the LEDs (or simply saving them), I suggest marking them for color. I used Sharpie markers and colored one side of the LED body.

To install a new LED, lay it face-up on your work surface and grasp it with the tweezers. Place it in position on the contact points (remember the cathode), and apply heat to the LED contact and the circuit board point simultaneously. The solder should soften, and the LED should settle down flat against the board. Now, with slight pressure on the LED, apply heat to the other end. If there was a mound of solder under it, the LED should settle slightly further.

Examine each end of the LED, using a magnifying glass if necessary. There should be a slight slope of solder against each end, giving strength to the joint. Remove any excess solder that may make inadvertent contact with other points on the circuit board. Repeat for each LED that is being changed or added.

Once all LEDs are in place, install the resistors. They are not polarity sensitive. There are several holes in the circuit board that may be used. Examine the board carefully to be sure the holes are in the copper trace that matches the resistor location. Some boards use surface-mount resistors as shown here, and some use conventional, cylindrical resistors. The procedure is essentially the same. Be sure to fit the resistors close to the board, and if necessary, bend them over toward the top of the board so they don't interfere with the gauge faces.

Once all components are securely soldered, plug the board into the bike and check that all LEDs light. If they don't, check polarity for each LED, and check all connections. Note that one LED with reverse polarity opens the circuit for one or two others. If they're all correct, a multimeter in resistance mode may allow you to test each LED for function by lighting it. Polarity must be observed. I had a bad one and found it this way.

If all is well, you may now reinstall the gauge faces and actuators. Start by aligning the ten pins of the digital displays, being sure to align the pins on the underside of the plastic frame with the holes in the board. Then, gently manipulate the needle to get the four pins of the actuator to drop in. They are very delicate, and no force should be applied.

Once all are in position, use a low-tension rubber band to hold the face and needle in place. Examine everything for proper position. Now you may resolder. Clean up the iron's tip and use only enough solder to make a good connection and a small cone on each lead. Double check your work. I did not reuse the four mounting tabs on the needle actuator out of fear of damaging them or the circuit board. Instead, I applied hot glue at each point to offer additional security. Now you may reinstall the two aluminum screws on each side (#10).

When both sides are complete, again plug the board into the bike. After a moment, both digital displays should function, and both needles should swing through their arcs as normal.

The circuit boards may now be reinstalled in the housing in reverse order. Before installing the front bezel, use alcohol and cotton balls to clean all fingerprints and dust from the gauge faces. Complete reassembly and plug the gauges in once more to admire your work. Reassemble the bike.

Finished! For my project, I used the clockwise LED color pattern blue-blue-blue-orange (stock)-red. I'm happy with it, though I do wish the red came through a little deeper. I don't mind the magenta, but it's just a bit 90's for my taste.