Stepper motor/LED's replacement 05 Tahoe
Not difficult at all if you have some mechanical and soldering skills. sorry i did not take any pics.
Disassemble: now let me try to remember how to do this: Do i need to go through the instrument cluster removal? once the cluster is out of the Tahoe, place it face down on the a towel (i did the work on the kitchen bar, good lighting). you will need a couple jeweler common screw drivers and/or scribes, a soldering iron, solder, flux and a solder sucker (to remove the solder from the old stepper motors). gently use the jeweler screw drivers to bend back the plastic tabs (4). then the guts will come away from the outer clear face. if memory serves, you will then have to remove the needles by gently prying them off. i used a 90 degree common screw driver with a tongue depressor under it (against the gauge face) and pried at the stepper motor shaft, they should pop off with just a little force. Now you can remove the circuit board from the face plate by again using the screw drivers to bend back the plastic tabs until the circuit board comes free.
now the fun begins, the stepper motors have four solder joints. you need to heat up each joint and remove the solder from it (use the solder sucker or if you don't have one you can use compressed air to blow the solder it away, careful where it goes it will be hot), could also use a shop vac with a very small tip. after you have removed the solder from all four joints the stepper motor can be removed. if it gives you resistance go back and check that all of the solder is removed, you don't want to break the circuit board!
Stepper motors: position the new stepper motor in the same configuration as the one removed. put a small amount of flux on the pins protruding through the circuit board. heat the pin and add a small amount of solder until it flows around the pin. do this for all four joints. then repeat for the remaining five stepper motors.
LED's: replacing the lights is a little trickier to explain: the original lights are soldered at two points (opposite corners)directly to the circuit board, no pins protruding. so you will have to de-solder the the joints and remove the old light. the new light have two wires (legs), bend them at 90 degrees in opposite directions. again lightly flux the legs and solder them to the spots where the old lights were.
here is the tricky part. the new LED's are directional specific, meaning they will not work if installed backwards. there is no reference (that i could find)for what way to install them, i found this out the hard way. you will need to plug the instrument cluster back into the car and check the light before you put the cluster back together. swap around any lights that do not work.
Reassembly: clean up any flux around the solder joints with Flux remover or rubbing alcohol. flux does a great job of cleaning the joint and making the solder flow, but it can be corrosive if left on the board. put the gauge face and circuit board back together, you may have to re position the new LED's (bend them at angles, they are taller than the old lights) so they clear the "clear plastic" on the gauge face piece. now put the needles back on the stepper motors, you do not need to be perfect on lining them up at their lowest indications, when you turn you vehicle on the gauges calibrate themselves automatically. i put them about in their "zero" positions. press on the center of the needles, you will feel them slide in as you increase pressure. when you do this put your hand on the back of each stepper motor to support it (don't want to break the solder joints or circuit board).
I would temp install the cluster minus the outer plastic face and check everything out before final assembly.
One note on the LED's: because they are taller they are closer to the gauge face plate. so there are areas on the gauges (except RPM) that are brighter than the rest. i did not like this and experimented on re-positioning the LED's several times but i could not fix this. now i just turn down the brightness on the instrument lights and it is less noticeable.
hope this helps let me know if i can add anything else......or if this is overkill
