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Weird Power problem


SM 2003
Full Member
Nov 23, 2002
Westchester, NY
I have a 2007 LTZ 6.0 with Nav & DVD. The following incident occurred last weekend and now more then ever. When starting the truck, the radio, navigation system, onstar and backup sensors were inoperable. Even the turn signal "click" was silent. The heat and air controls worked as well as all the gauges on the dash.  The only way to get everything back is to restart the after opening and closing the door.

Has anyone had a similar situation happen to them?

Dealer tested for "trouble codes" but it looks like the restart cleared the  memory.
I had exactly the same problem with mine yesterday. Do you have a lockpick from coastal-tech installed? I restarted the truck 4 times yesterday before the problem went away. The following info is from the GM Service website


Subject: Diagnostic Information on Navigation Radio Aftermarket Modules Causing Various LAN Communication Concerns/DTCs, No Crank, Vehicle Stability Lights/Messages, TPM Warning Lights, PRNDL Position Errors #07-08-44-004 - (02/26/2007)

Models: 2007 Cadillac Escalade Models

2007 Chevrolet Avalanche, Silverado, Suburban, Tahoe

2007 GMC Yukon Models


Some customers may comment of one or more of the following concerns:

    ?  Vehicle will not crank.

    ?  Vehicle cranks but will not start.

    ?  Vehicle stability enhancement system warning lights and messages.

    ?  PRNDL gear indicator position errors.

    ?  Tire Pressure Monitor (TPM) system warning lights.

Technicians may find various Local Area Network (LAN) communication Diagnostic Trouble Codes (DTC) and no low speed LAN communications with the Tech 2?.

These conditions may be caused by the installation of an aftermarket navigation radio module.

It has been brought to our attention that some customers may be installing and using certain aftermarket products that are used in conjunction with the factory navigation radio systems.

The product allows the user to display the video output of the DVD player on the navigation screen. Normally the DVD output is only available on the navigation display when the vehicle is placed in PARK. The product allows an aftermarket camera or second backup camera and enables navigation functions that are only available in PARK.

Dealers have found that these products can cause unusual problems that are difficult to diagnose. These products may be difficult to identify because they are installed behind the navigation unit and are not visible unless the navigation unit is removed.

If you suspect that the customer has installed aftermarket products of this nature and you suspect that the product may be the cause of the concern, you should ask the customer if any vehicle modifications have been made.

Additionally, if the customer's information is not available, you may want to test the navigation and DVD system to see if normally blocked functions are available with the vehicle in DRIVE. Removal of the navigation radio will also allow you to verify if one of these products has been installed.

Warranty Information
Warranty coverage does not extend to problems created by aftermarket devices. Damage to normally covered systems caused by aftermarket products is the responsibility of the customer or the aftermarket installer.

SovereignMgmt said:

I'm having the BCM flashed in the morning and hoprfully that will fix it.

I have ordered the free Version 3 lockpick upgrade for mine ( I have version 2), as soon as I get it I will let you know if it solves the problem on mine
Same thing happened to me this past weekend. Radio and Nav system completely blacked out/inoperable and the turn signals (although they were working) had no sound. Everything else worked just fine. I tried restarting a few times which didn't fix it. I then popped the hood and started pulling/checking fuses. Nothing was blown and then tried to restart and it all came back on just like normal. I have no idea what the problem was. I don't have a "lockpick". Just stock from the factory. Would like to know if more people have had the same problem and if anything fixed it.
I have all the problems that have been described in this thread.
I also have a gen2 lockpick installed - I have been trying to get the gen3 lockpick, but Coastaltech will not respond - thier website gives me a  "You are not authorized to access the Shopping Cart!"
It looks like if you complain about Coastaltech they will dump you. I cant get my upgrade to see if this corrects my problems.
impact said:
I have ordered the free Version 3 lockpick upgrade for mine ( I have version 2), as soon as I get it I will let you know if it solves the problem on mine
I have had the new unit installed for about a week and every time I start the truck it has worked properly, No More Electrical Problems :D
How do you get a lockpick.  I would love to be able to watch the dvd or do the nav when not parked
I am in the same boat as you - manual operation does not work and coastal tech does not help you out.
I got one email back from them after over 20 emails and a dozen phone calls that said "send your unit back for refund" (like i will ever see the refund- see other posts of not getting refunds)
I am wanting to try the gen3 to see if this corrects the problem but I have been blocked by the coastaltech site.
It seems that if you make a complaint about their product, they block you from their site. What a way to handle business???