How-To: Gauge Cluster Stepper Motor Replacement GMT800.

lowcountry · March 7, 2011

A few months ago I was plagued with eratic voltage.

http://www.gm-trucks.com/forums/index.php?...c=124932&hl

Here was the fix.

2003-2005 GM vehicles have had a recurring problem of stepper motor failure in the gauge clusters. Gauges will have jerky movements, show the wrong reading, and/or fail. My voltage gauge did all of those. The dealer wants $600, you can buy fixed ones off ebay for $300, send yours off and have it fixed for $90 plus back and forth shipping, or fix it yourself buy ordering six motors yourself for $40 shipped. If you are scared of doing it yourself, I recommend sending it off. Your truck will run without the cluster, just make sure you keep gas in it. I also had a burned out bulb in mine so I ordered some of those too. I have never done any electrical work on this small of a scale and I was a little nervous. This kind of work requires a low wattage soldering iron. I picked up a 15w from Radio Shack along with some smaller solder and soldering wick. The wick is used to soak up the existing solder on the board and does a great job at it.

So here we go. As always, you should disconnect the battery even though I didn't.

First off, remove the bezel. You need to tilt the steering wheel all the way down and shift the gear lever all the way down.

Now you have access to the 4 6mm bolts that hold the cluster in. Unbolt them, pull the cluster out, turn the key off and put it back in park, and unplug it.

Here is the cluster with the required tools.

Turn the needles counter clockwise until they stop. Then mark their position.

Using a fork, keep turning them counter clockwise and apply pressure. The needles just pop right off.

Using another fork will help get some leverage.

Pic of the cluster with the needles removed.

Here is a pic with the face removed. As you can see, all the stepper motors are the exact same. They are just mounted in different positions. The space in the lower left where there could be a motor is for a transmission temperature gauge for other vehicles.

Here is the backside of the board. This where you desolder and resolder the new motors.

This bulb had burnt out so I desoldered the socket and took the old one out and dropped the new one in.

Then resolder the old socket with the new bulb. This was a dollar fix.

Install the new motors and bend the pins in. Then solder them in.

Install the needles in the 12' o'clock position.

Then rotate them counter clockwise to the marked positions.

Reinstall the gauge back in the truck without the protective lens and make sure everything works. I ended up tweaking the voltage gauge a hair to make it dead on. Reinstall the protective lens and the bezel. I took it for a spin and discovered the speedo is 1.5mph on the low side. I can live with that.

whajac · March 28, 2011

Very nice write up. Thanks for the detail, how many connectors for each motor? I've got this repair in my future.

rws265 · April 11, 2011

Thanks for the great how-to. My oil pressure gauge has gone nuts. I'm gonna replace all the steppers myself now.

diggemsmax · May 3, 2011

I replaced all 6 of my stepper motors, I have all of them set correctly except for the water temp(highly important gauge). It will not move after engine is warmed up. I have tried and tried turning it counter-clockwise to zero. It does jump when I insert wiring harness but not to the 160 mark. Yes I used my GPS to verify my speedometer it was very helpful (don't need a ticket)! Any ideas on how to get the water temp gauge working properly?