Gauge Cluster Repair

[Project Denali]

Hey everybody, here with another thread on fixing my heap haha.

Last night and today I did a DIY fix on my 2004 Denali gauge cluster. I had a large parasitic draw through the "IPC/DIC" circuit as well as multiple issues with my cluster. As you can see it needed attention...

After much research, I ordered a kit with the approved steppers, new bulbs, etc. After soldering in all the new motors and resoldering the PRNDL I decided to check my work. Every gauge as well as the PRNDL display are flawless now (still need to do the lights) yet my tach is waaaaaaaay off.

Do you think it's the stepper motor or a deeper electrical issue? Isn't the tach getting it's signal from the ECM?? If so idk how it could be anything but a bad stepper. Any help much appreciated. Wondering because it also got stuck above 4000 RPM before but, it would move back down some... With the new motor, it is stuck all the way like it is pegged out and will not go back towards 0 at all... Also, let me know if you guys think I should make a thorough "Cluster Repair Thread"...

 

[mals]

After much research, I ordered a kit with the approved steppers... yet my tach is waaaaaaaay off. Do you think it's the stepper motor or a deeper electrical issue?

You might want to check the solder points of the tach's stepper motor. When I did mine, after reinstalling the cluster my fuel gage would swing negative when powered up. I pulled the cluster and was about to desolder the stepper to return it when I noticed the bad joint on one of the pins. It redid the solder, turned the stepper by hand until it bottomed out, and reset the needle so it was below the first line on the gauge like the others. When I reinstalled the cluster, the stepper cycled normally, and the position was calibrated like the others.

Hopefully it is that simple for you. If not, I would suspect the stepper motor as well. A simple test would be to swap it with another stepper in the cluster that you know works, and see if the issue follows the swap or stays with the tach.

 

[Project Denali]

You might want to check the solder points of the tach's stepper motor. When I did mine, after reinstalling the cluster my fuel gage would swing negative when powered up. I pulled the cluster and was about to desolder the stepper to return it when I noticed the bad joint on one of the pins. It redid the solder, turned the stepper by hand until it bottomed out, and reset the needle so it was below the first line on the gauge like the others. When I reinstalled the cluster, the stepper cycled normally, and the position was calibrated like the others.

Hopefully it is that simple for you. If not, I would suspect the stepper motor as well. A simple test would be to swap it with another stepper in the cluster that you know works, and see if the issue follows the swap or stays with the tach.

A second look is always good! Removed it to solder in my new lights and checked the tach stepper. All 4 points had good solder except one wasn't making contact due to a broken "solder pad" on the board. So I reflowed it and made it stretch a bit longer. Popped it back in and bam, everything is looking really good! May have to adjust my speedo but I'm happy now haha.

 

[DustyJohns]

My PRNDL is almost not visible because of how dim it is. Do I need to replace the switch like you did? Or is it simply a bulb?

I appreciate your write up with the pics and links.

 

[Project Denali]

Oh, I didn't replace the switch, just replaced my stepper motors and backlight bulbs. From my experience and research I would almost bet money it's just the resistors. If you want, take your cluster apart and check out the cluster of 7 resistors that control the PRNDL and I bet resoldering them makes it work again! They get too hot and the solder joints crack ever so slightly. Sometimes they even visibly discolor the surrounding area. This is what you're looking for.

And a closer view... (the 7 resistors are slightly above and to the left of the soldering iron)

 

[mals]

My PRNDL is almost not visible because of how dim it is.. is it simply a bulb?

I would almost bet money it's just the resistors. If you want, take your cluster apart and check out the cluster of 7 resistors that control the PRNDL and I bet resoldering them makes it work again!

I had the same issue with my PRNDL display being very dim. I reflowed the solder of the surface mount resistors @Project Denali pointed out and the display is back to full brightness.

I watched a few YouTube videos on stepper motor replacement, bulb replacement, and PRNDL dimness before I cracked my display open. Most are not well filmed, but cumulatively they walk you through the process.

 

[DustyJohns]

Awesome! Thanks you guys.