15663A - SERVICE UPDATE (REVISED SPECIAL REPAIR TOOL ADDED). RELOCATE A WIRE CIRCUIT WITHIN THE ONSTAR CONNECTOR. THESE VEHICLES LACK A GROUND IN THE MICROPHONE RETURN PATH, WHICH RESULTS IN THE VOICE RECOGNITION BECOMING INOPERABLE WHEN THE VEHICLE IS IN RETAINED ACCESSORY (RAP) OR ACCESSORY POWER MODE. IN ADDITION, THE HANDS-FREE VOICE QUALITY CAN BE DEGRADED. THE ONSTAR FUNCTIONS ARE NOT IMPACTED BY THIS CONDITION.
