Intro: How to Repair a GM Speedometer
Do you drive a GM car (200 and up) and have gone past 70-80 thousand miles only to have your gauges (speedo, temp, and fuel) go out on you? Don't want to pay the $500 (more/less) that the dealer or shop will charge you? then read on and save a few hundred bucks and have the piece of mind that you fixed something on your car yourself.
I had to pay for this info when this problem happened to me several years ago, but I feel that people should not have to be taken advantage of when it comes to the repair work of the car.
I have been contacted by the person who I bought this information from and I have removed his photos, ALL OF THE PHOTOS IN THIS INSTRUCTABLE ARE FROM MY CELLPHONE CAM.
But if you like PLEASE HELP SUPPORT THIS MAN AND HIS FAMILY BY BUYING THE REPLACEMENT PARTS FROM HIMHERE
Step 1: How to Repair a GM Speedometer
Here are the tools that you are going to need
1. Soldering Iron
3. Needle nose pliers
4. Multi tool ( or a small screwdriver/something with a small point to it for prying)
5. Solder bulb
6. Regular Kitchen Fork
7. Masking tape
8. New replacement motors( PLEASE HELP THIS MAN SUPPORT HIS FAMILY BY BUYING THESE AT HIS WEBSITE HERE) or you can GOOGLE NEW REPLACEMENT MOTORS , your choice.
1. Replacement Stepper Motors -
Available from Dr.Speedometer in any quantity plus upgrades for your gauges. PLEASE HELP SUPPORT THIS MANS FAMILY BY ORDERING THESE PARTS from this link here drspeedometer.com
If the link doesn't work, you can google gm replacement motors or Ebay it
Example speedometer is from a my 04 Impala. Yours may vary in appearance, and have more motors, but the procedure is basically the same for all 03-06 GM instrument clusters.
First, remove the clear plastic lens by gently prying outwards on the black tabs, use the Multitool. Or screwdriver , or whatever it is you are using.(disregard the two wires sticking out of the cluster, those are form my LED'S that I put in)
Here is the unit with the cover removed, Remember that when you do this the button that you used to reset your tripmeter / look at you actual miles will "pop" out because it is spring loaded, remember after you put all of this back together to put the spring and button in BEFORE you put the plastic lens back on
Now tear off several short pieces of low tack masking tape, one for each gauge.
Rotate each needle counter clockwise until they come to their stopping point. Stick the tape to the gauge face plate directly below the needles. Look straight down on each gauge and make a mark directly in line with the tip of the needles. These marks will give you a reference point to set your needles back exactly where they were originally after you replace the stepper motors, ensuring accurate readings upon reinstallation.
BE VERY CAREFUL WHEN YOU ARE DOING THIS, IF YOU MESS UP THESE GAUGES WILL NOT READ CORRECTLY AND YOUR SPEEDO/ OR OTHER GAUGE WILL GIVE A INCORRECT READING!!
If you need to grab a sharpie with a thick enough tip so that it is the same size as the point of the needle so you don't mess this step up.
Break each needle loose from the shaft by firmly rotating it counter clockwise a couple inches
Now slide the fork under the gauge base being sure the fork tines are going around either side of the shaft. Next, pry upwards on the gauge base by pressing down on the fork handle. Be careful not to scratch your face plate. Pry firmly but slowly and the gauge will slide upwards and off the shaft. Move on to each gauge using the same technique.
Remove the black back cover from the white inner frame by gently prying outwards on these black tabs
Now remove the circuit board from the white inner frame. It will pull off easily.
Here you can see the 3 white stepper motors on my Impala cluster
this is what your new replacement motors will look like. Do NOT buy the cheap BLACK Chinese ones, they are just as bad if not worse than the stock ones.
one of the four solder points that each stepper motors has. you will have to de-solder each one of these to get the motor out.
Now melt the solder on one of the solder points, as soon as the solder melts use the solder bulb to quickly suck up the melted solder. This may take a couple tries.
1. Try not to apply more heat to the board than is necessary to quickly melt the solder.
2. Also, do not touch anything else on the board with the hot iron and
3. Don’t let any melted solder drip onto any component leads which could cause a solder bridge and potential cluster failure. (This last step is VERY IMPORTANT! IF you get solder on the leads and your cluster fails you will have to buy a new unit, if you do not feel like you can do this , get a buddy that can for you, you have come too far to mess this up!)
After you De-solder the connections make sure that none of the solder is stuck on the board
After removing the solder from all 4 points of the motor straighten the motor’s 4 wires using needle nose pliers from your multi-tool, this will make it easier to pull the motor off. Now remove the motor from the circuit board by pulling firmly on the motor body being careful not to damage any other components on the circuit board such as the lamps. Repeat these steps for the remaining stepper motors that you choose to replace.
Now align the plastic posts and the 4 motor wires with the holes in the circuit board and slide the motor onto the board. Because one plastic post is larger than the other each motor can only be installed one way eliminating any worry about installing them backwards. After installing the motors flip the board over and bend the wires over slightly to help hold the motors to the circuit board while soldering. ( do not have photos of this cause I do not want to de-solder and then re-solder my motors back on ....sorry guys)
Now solder the motors to the circuit board,Be careful not to drop solder on any of the component leads on the back of the circuit board to prevent a solder bridge which could cause cluster failure.
Place the repaired circuit board back on the white inner frame and snap the black backing in place to hold it all together.
Now re install all of your needles in roughly the 12 o’clock position (exact position is not critical.) also make sure that you have them firmly pressed in , but not so pressed in that the motors will not move the needles
Now rotate each needle counter clockwise until it lines up with your mark. If you accidently go too far simply keep rotating counter clockwise until you get back around to your mark (REMEMBER IT IS VERY IMPORTANT THAT YOU LINE THOSE NEEDLES UP TO THE ACCURATE LINES THAT YOU MARKED IN TAPE OR ELSE YOUR UNIT WILL READ INCORRECTLY) Next, remove your pieces of tape and put the spring back in its place followed by the milage reset/ trip button, now reinstall the clear lens.
Congratulations!!! you have just repaired your cluster and saved time/money/ and headaches from the dealer!!