03-06 Led Gauge Cluster Mod

reiling3 · January 17, 2009

After hours of searching for this mod was only able to find it on two websites, none of which were this one. Fullsizechevy.com and Dieselplace.com where the only ones I could find.

It all started with the whole speedo stepper motor and since my truck isn’t covered due to the 86k miles on it, and I didn’t want to pay the 425 bucks the local dealership wanted I decided to change the motor myself.

Being the preventive maintenance kind of guy I figured it would be a good idea to change out all six. That turned out to be way easier than I could have hope and save myself a lot of beer money.

During the motor replacement process I notice the several gauge lights that were burnt and decided it would be a good idea to make those into LEDs. But, since those are regular 12v incandescent bulbs I knew I had quite the task ahead of me. So after hours of research and refreshing my mind about LEDs and resisters (it has been 5 years since my last electronics class) I felt confident enough to do it.

Technical Info

I order my LEDs from superbrightleds.com. They have a plethora of different bulbs to choose from. I chose the Super White LED 5mm, 4500mlm, with a 360 degree viewing angle. The huge viewing angle reduced any chance of hot spots on the gauges. They cost a little more but are worth it. Just ask the guy on fullsizechevy write up.

Since the incoming voltage is 12v resisters are needed to drop the voltage to the three volts the LEDs need to operate or they make smoke….trust me on this one.

Instead of using math I just used a calculator on the internet to find my resistor values. With my 9 lights at 3.3 volts 20ma and I used 14.4 as my voltage just to be safe; I came up with ½ watt 560 ohm resisters. So I just ran to my local Radio Shack and got 15 of them for less than 3 bucks. Spares are always handy to have.

Tools used

Weller 25watt Soldering Iron

Very small rosin core solder, I used .022" I got at Radio Shack

Small side cutters

Small pliers

Small gauge wire stripper

9 volt battery

Pieces of small wire, i used a chunk of CAT 5 I had lying around

A. Cluster Removal

NOTE: READ Whole article before starting, especially final assembly section

Sorry no pictures, but its fairly simple and straight forward.

1. Remove dash trim piece, mine pops right off since it has been off so many times.

2. Remove four screws 8mm I do believe

3. Put gear selector all the way down. CAUTION vehicle will roll if on a slope

4. Pull out cluster part way, reach back and squeeze blue thing on the harness and gently wiggle back and forth. There is a lot of pins there so be careful.

5. Once harness is off the cluster will come out with a little maneuvering.

You are able to drive your vehicle with the cluster out. You just don’t have any vitals. I drove mine to work for a week without any problems. I do have a Scan Gauge so that gave me my important info. As long as I didn’t run out of fuel I was fine.

B. Cluster Disassembly

I would suggest a well lit clean workbench. (Living room coffee table in my case)

Sorry no pictures again but not too hard.

1. Basic physics tells me that plastic is brittle when it’s cold. So if your cluster is cold like mine was (negative temps in Southwest Montana) I would suggest letting in warm up to room temp.

2. Remove front black bezel. There are clips on the top and bottom that attach to the white center piece. A flat screwdriver and some gentle massaging it all it takes.

3. Removing Needles. A regular kitchen fork worked the best for me. Just insert and gently pry up.

4. The back piece comes of easier than the front, just a few more clips

5.Then the rest pretty much falls apart after that.

C. Removing Bulbs

Using my soldering iron I just hit them for a few seconds right next to the little blue cradles that hold the bulbs. There are four solder spots for each bulb but only two are holding the bulbs in. Once you get each corner they pop right off.

Once the bulb where removed I wanted to be sure which of the connections were my positive 12v and negative ground. So plugged just the circuit board back in (blue clip on harness facing down) and using a 12v test light I just checked each bulb location for my positive 12 volts and put a small dot next to it with my Sharpie.

I cut each resister down on one end and soldered that straight up to the positive connection for each bulb. Then I bent each of the bulb leads to fit properly next to the resistor while keeping them as low as possible. Remember LEDs are polarity sensitive. So it is important that they are installed on the correct positive and negative terminals for them to work.

Notice resistors and sharpie marks

Bent leds

Notice Positve and Negative

Once they are all soldered in I put the white plastic piece on top to be sure they weren’t too tall.

To test them I soldered some wire onto the terminals where the bulb for the trans temp would go (I don’t have a trans temp gauge) and hooked up a 9v battery to it. And to my surprise they lit right up.

Then I took it out to my truck just to double check and made sure they still worked properly. They are even dimmable.

D. Final Assembly

Put everything back together as you took it apart but leave the needles and front cover off.

This is where it gets tricky. Somehow you need to be able to put the needles back into there correct location. I am lucky enough to have ScanGauge so I was able to set all my needles back except the Oil pressure and Fuel level. For the oil pressure I warmed up my truck to operating temperature and marked where the needle was. For the fuel level I just filled up my tank when I was done and put the need on the full mark. For everything else that’s up to you. I would suggest using a GPS to set your speedo and checking your idle rpms before you remove the dash and then you can just set it back with the vehicle idling. My was right around 900rpm. The voltmeter should be around 14.5 or so when idling and the temp gauge around 190 when completely warmed up.

Other Tips

1. Soldering iron is HOT and you will melt things you shouldn't, so watch were you are putting it

2. Always make sure any pieces of wire are not touching parts they shouldn't be.

3. Make sure you clip off any excess of the wire that were soldered.

4. Before testing with power, shake the crap of the assembley so any pieces of solder or wire are out of there.

5. Don't blame me for anything you did wrong, this is just a guide, I am not resposible if you fry your guage cluster. If you don't feel comfortable doing it then you problably shouldn't.

I'll have final installed pics posted shortly.

Any questions or constructive criticism are appreciated.

Edited January 17, 2009 by reiling3

stadt11 · January 17, 2009

Nice Writeup Ryan

I look forward to your final pics

reiling3 · January 17, 2009

Here is a night pic of the the dash.

The light is very even and no hot spots.

I am really impressed on how it looks. It is almost a blue light, it kind of clashes with the rest of the lights. I guess I'll have to work on the radio and the HVAC next.

I also did a mod on my Bright Headlight indicator light. As most of you know that light is very bright especially when you are driving for long periods of time with very little oncoming traffic. So i fixed that problem.

I Just took one of my extra resistors and put it inline of the led.

A word to the wise....this led is extremely small and hard to work with. It took me a few time to get the solder to stick.

I ran the resister down into the area where the trans temp would be. Other wise there wouldn't be enough room. Note: the loose wires on the left of the resister are what i used the test my leds, that is where the trans temp light would go if i had the gauge

I used a little duct tape to hold it in place and thats all it took.

Edited January 17, 2009 by reiling3

MarkD · January 17, 2009

Nice Job, what was your final cost?

reiling3 · January 17, 2009

Nice Job, what was your final cost?

It was actually really cheap, around 20 bucks for LEDs, resistors, and solder. I had everything else lying around. The most expensive part was just the labor. I easily had a couple of hours between redoing and double checking everything so it worked right.

catchfast33 · March 12, 2009

Nice Job, what was your final cost?

It was actually really cheap, around 20 bucks for LEDs, resistors, and solder. I had everything else lying around. The most expensive part was just the labor. I easily had a couple of hours between redoing and double checking everything so it worked right.

how did you take the needles off did you just pop them off or turn them pop them off

MikeInCtown · March 13, 2009

FWIW with the needles:

I've read through a lot of links through various suppliers for the guage clusters, stepper motors and guage faces. I have borrowed the instructions from another site:

You will now have access to the gauge needles.
**IMPORTANT TO FOLLOW CALIBRATION STEPS PRECISELY***

Place tape at the end of each needle.

Turn each needle counter-clockwise until it stops as shown below and then mark off the location on the tape with a pen. If you do this, you should have no issues with calibration when you reassemble.

Once you have your positions marked, turn each needle counter-clockwise until it breaks free from the shaft. Then use a fork to pry each needle off. It will take a little force, but just be slow.

Then, once you replace the stepper motors you put the needles back on like this:

Now press each needle back on in the 12 o-clock position. Then turn each needle back to your mark on the tape. If you miss the mark just keep turning counter-clockwise until you come around again.

To test things out, plug the wiring harness back to the cluster. You should immediately see the needles jump down and then up to the original 'zero' points.

I found these instructions from Trailvoy website

There is also at least one seller on eBay who says they will give instructions on replacing the motors as well.

catchfast33 · March 19, 2009

FWIW with the needles:

I've read through a lot of links through various suppliers for the guage clusters, stepper motors and guage faces. I have borrowed the instructions from another site:

You will now have access to the gauge needles.
**IMPORTANT TO FOLLOW CALIBRATION STEPS PRECISELY***

Place tape at the end of each needle.

Turn each needle counter-clockwise until it stops as shown below and then mark off the location on the tape with a pen. If you do this, you should have no issues with calibration when you reassemble.

Once you have your positions marked, turn each needle counter-clockwise until it breaks free from the shaft. Then use a fork to pry each needle off. It will take a little force, but just be slow.

Then, once you replace the stepper motors you put the needles back on like this:

Now press each needle back on in the 12 o-clock position. Then turn each needle back to your mark on the tape. If you miss the mark just keep turning counter-clockwise until you come around again.

To test things out, plug the wiring harness back to the cluster. You should immediately see the needles jump down and then up to the original 'zero' points.

I found these instructions from Trailvoy website

There is also at least one seller on eBay who says they will give instructions on replacing the motors as well.

okay i have gotten everything but the led themselves and this because i dont know which ones to choose between they list like this

1~9 10~99 100~499 500~999 1000+

which ones do i need to get

MikeInCtown · March 19, 2009

I think that just means pricing as to how many you intend to buy.

10-99 pricing is different than you would get buying 1000+ bulbs. They certainly aren't wattage or lifecycle numbers.

catchfast33 · March 19, 2009

I think that just means pricing as to how many you intend to buy.

10-99 pricing is different than you would get buying 1000+ bulbs. They certainly aren't wattage or lifecycle numbers.

okay thanks man i just makin sure i will post some pics of what mine looks like when i get done im also doin the hvac and light control as well

catchfast33 · March 24, 2009

I think that just means pricing as to how many you intend to buy.

10-99 pricing is different than you would get buying 1000+ bulbs. They certainly aren't wattage or lifecycle numbers.

okay thanks man i just makin sure i will post some pics of what mine looks like when i get done im also doin the hvac and light control as well

okay i am faced with this problem the guy in this forum got the 4500 mlm i have bought the 11000 mlm with this cause hot spots in the lighting they are still 360 degree viewing angle they are just brighter

catchfast33 · March 27, 2009

okay i finally finished and very satisfied with the out come here is it

coyote05 · April 3, 2010

Nice writeup, a couple things to add.

If you are doing all the bulbs on the cluster including the turn signals and cruise lights you need 11 otherwise 8 LEDs. The HVAC (manual dual climate) controls need 8 also. Headlight switch needs 1, 3 if you are adding two for the unlit section, link below. 1 for the outside bed light also.

The link below also provides all the resistor placements except for the outside bed light which I don't think he did. I had burn marks on the some of my plastics from the bulbs. The bed light and cluster will turn blue, while the headlight switch and HVAC controls will stay white because the bulbs had blue plastic over them. So you may want to look around for blue LEDs and replace them all with blue instead of white. I can no longer control my illumination, but I need to take my head light switch back apart because I could before I did that switch and that one took the longest since I had to add two bulbs where there weren't and and you have to keep it away from the illumination dimmer.

You'll need one 470 ohm resistor if you add the two other headlight switch LEDs because they'll be in series with each other. You could actually use as low as 470 ohm resistors for this whole project if you buy the white 360 degree LEDs from superbrightleds.com otherwise you'll want double check your resistor values here. http://led.linear1.org/1led.wiz

http://silveradoss.net/default.aspx?g=posts&t=511

Edited April 3, 2010 by Coyote05