After having both my factory nav and the dealer purchased replacement nav in my 07 H3 suffer the flickering problem, I believe I may have it solved.
Changing out the battery terminals was a good upgrade, even with no problems in the nav.
My "fix" was with Carbon Conductive Grease. The main connector on the back of the nav/radio is not a quality jack, the female pins don't seem very strong or tight.
The connector also deals with more moisture and condensation than I ever considered
It is right in front of the main vents for A/C and heat, which could contribute to the problem. Changing out the female connector is a option, but rather involved
This factory nav also gets a feed from the light switch, to dim or brighten the display.
I put the conductive grease in all terminals (24) and wiped the face of the connector clean.
It has not flickered in over two weeks. Yes, a short time, but longer than all my other feeble attempts at fixing this problem.
This post started back in July 2010. I hope I'm not necro-bumping too badly
I just don't want anyone to go through all the hassle and expense that I did. Tram, are you out there ?!?

Original thread
https://www.hummerforums.com/forum/h...-screen-24593/

 

Hope the flickering issue is gone. I know you had one heck of a time trying fix after fix with no success.

 

I would be embarrassed to tell what I spent to get to this point.

 

I too am experiencing this. It started with flickering on and off all the way home from work. Then eventually went black. Everytime I restart the engine, it flickers for a few minutes then goes black. I followed your advice and put some conductive grease in plug, didn't seem to help.

Still considering options. Can corrosion on battery terminals really cause the flickering?? Can't see that.

 

Corrosion on battery terminals is a problem even if you don't have a flickering screen.
If you read all the responses, I went thru the entire process of new terminals, new battery and lastly a new nav system head unit. And it started flickering again.
The conductive grease has solved my problem. About one month now
Electronics can be very sensitive to voltage changes and a good connection to the battery terminals is imperative.
You did use carbon conductive grease, not die-electric grease, yes ??

Did you use any contact cleaner on the harness connector first ?
That is an important first step. Also examine the female contacts and the head units male contacts and make sure they are in good condition.
Short of all this, I don't have an answer for you.
I still believe the connector is the lone culprit in this problem
Good luck

 

Actually, I used the di-electic grease. Guess I could clean it and try again. I did notice the plug doesn't feel overly tight when plugged in like one would think it should. I'll try cleaing it up and trying to tighten the female side again, as well I'll clean the battery terminals up. Any idea where one would buy a new harness plug to replace the current one?

 

Die-electric may be the problem it is the opposite of the carbon conductive grease
Spray connector well with contact cleaner now, you need to get all of the die-electric OUT

I also ended up slightly (be careful here) bending the male pins in a slight arc but kept the point of the pin in the same position and create and tighter fit in the harness connector.
That was a touchy job, but it made the connector go onto the pins in a tighter way

The harness connector is a proprietary plug/harness from Delphi or some other GM subcontractor. Finding a new one would be almost impossible, short of someone having a wrecked H3 in your year

 

OOPS! Someone forgot to read the package!

Dielectric grease is a nonconductive grease. Because it is nonconductive it does not enhance the flow electrical current and actually impedes it. Electrical conductors should NEVER be coated with dielectric grease prior to being mated. However, dielectric grease is often applied to electrical connectors, particularly ones which contain rubber gaskets or plastic, as a way to provide a nonconductive lubricant and sealer for the rubber/plastic portions of the connector.

 

And jpenny will have some difficulty getting all that grease off the connector.
It is also designed to stick what it's applied too.

Tainter- nice description, who needs wikipedia

 

I would try brake cleaner to get the dielectric out of the connector. Just make sure you have your BATTERY DISCONNECTED just in case.