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Head Unit Replacement

Oddball_one

By Oddball_one
in Ask A GM Technician

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Oddball_one New Member

Oddball_one

Posted
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I've been having problems with my 18 Denali for a while. Fairly certain I have a lemon but that's another story. I took the truck in for service a couple of months ago and GM tech verified the Nav unit was flaky. Two month wait for a replacement warranty part (Radio Unit) and I finally get a call to bring the truck in for service appointment.10:00 AM on Tuesday. I know the book time says 5 hours so Expect a call at the end of the day. Well, I got a call at 1:00 PM telling me my truck was ready. First clue something was wrong. I then picked up my truck and noticed all my radio stations, Bluetooth connections,  and configurations persisted. There was a screen protector over the screen...That was crooked. Anyway I just looked at my Sirius radio ID on my emailed maintenance report and its still the same. Starting to seriously thing the tech didn't change the unit and BSed his way through the work.  My questions are:

 

1. If the head unit was replaced should I retain my settings?

2. Is the Sirius module separate of the head unit?

3. How can I check my ID numbers on my head unit. Any way to see what was initially installed on my truck?

 

Thanks!

Jsdirt Senior Enthusiast

Jsdirt

Posted
Posted

These newfangled devices are way outside of my wheelhouse. I would take it to another shop to verify the repairs. They may have just swapped some magic box inside your old unit that didn't affect all your presets, etc.. You're wise to be skeptical, however.

tbarn Senior Enthusiast

tbarn

Posted
Posted

There is no "NAV" unit or head unit. You have a radio (with sirius/xm if equipped), Onstar module, Human machine interface module (HMI) and a display module. It seems from your description that they replaced the display module. It's only function for entertainment is to display information and be a touch screen. NAV system is done with the HMI module. Presets are stored in the radio module.

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Jsdirt Senior Enthusiast

Jsdirt

Posted
Posted (edited)

.

Edited by Jsdirt
Jsdirt Senior Enthusiast

Jsdirt

Posted
Posted
4 minutes ago, tbarn said:

There is no "NAV" unit or head unit. You have a radio (with sirius/xm if equipped), Onstar module, Human machine interface module (HMI) and a display module. It seems from your description that they replaced the display module. It's only function for entertainment is to display information and be a touch screen. NAV system is done with the HMI module. Presets are stored in the radio module.

Way too many magic boxes for me there ... ?

Jsdirt Senior Enthusiast

Jsdirt

Posted
Posted

Don't I know it ... ?

Frankielozano214 Senior Enthusiast

Frankielozano214

Posted
Posted

I’ve swapped my screen a few times, the setting never change. As for swapping the modules that I would think reset your settings I know when I did the AppleCarplay upgrade they change the XM radio ID number. So I had to call and connect it to my new one

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