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For 1990-2009 cars only

Radio Displays Locked Or Theft Lock - keywords inoperative loc no sound speaker volume

Subject:Radio Displays "LOCKED" or "THEFT LOCK"

Models:2007-2008 Cadillac Escalade, ESV, EXT
2007-2008 Chevrolet Avalanche, Silverado, Suburban, Tahoe
2007-2008 GMC Sierra, Yukon, Yukon Denali, Yukon XL, Yukon Denali XL



This PI was superseded to update model years and Recommendation/Instructions. Please discard PIT4007A.


The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:

The radio theft deterrent system disables functionality if the VIN information received by the radio does not match the vehicle VIN information. The radio receives the vehicle VIN information through GMLAN. If a radio is replaced or swapped from another vehicle the radio will need to relearn the VIN information from the vehicle before it will function. If the VIN information of the vehicle does not match the learned VIN information in the radio, it will display "LOCKED" or "THEFT LOCK".

Recommendation/Instructions:

Currently, performing the radio setup in SI (Document ID # 1745049) will not learn the vehicles VIN information to the new radio. Engineering is aware of this and working on a correction.

A temporary solution is to perform the radio setup in SI (Document ID# 1745049), as well as, perform a VIN relearn. To perform the VIN relearn, build the Tech 2 as follows:

 

F0: Diagnostics

2006

Passenger Car

(1) Chevrolet

W

WN Monte Carlo LTZ

F6: Body and Accessories

Entertainment

F5: Module Setup

F0: Radio

F0: VIN Relearn

 

The Tech 2 will ask you if you would like to erase the theft data: "select yes"

 

Shut key off for 60 second and remove Tech 2 from vehicle.

 

VIN should relearn on start up.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.