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EQ Settings for U65 and U66 Amp RPO Codes - keywords classical country custom EQ1 EQ2 EQ3 EQ4 EQ5 EQ6 EQ7 equalizer inoperative jazz missing pop radio rock talk

Subject:EQ Settings for U65 and U66 Amp RPO Codes

Models:2005-2006 Chevrolet Corvette



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

Condition/Concern:

Some customers may comments that EQ7 is not an option on the radio per the owner's manual. This is due to a Owner's Manual error.

Recommendation/Instructions:

The available EQ options are listed below based on the AMP RPO code. Owner's Manual corrections are in place for future model years. Below are the normal operating characteristics of the EQ feature based on the AMP RPO code.

    • Base Audio System (U66 Delphi) the EQ options are:
        Custom, Classical, Pop, Rock, Jazz, Talk, Country.
    • Uplevel Audio System (U65 Bose) the EQ options are:
        Custom, EQ1, EQ2, EQ3, EQ4, EQ5, EQ6

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.