Audio System - Popping/Screeching Feedback Condition
TSB 09-5-903/23/09
THX AUDIO - POPPING, SCREECHING, FEEDBACK
NOISE, NO AUDIO - COLD START-UP - DEFAULTS TO
STEREO AFTER KEY CYCLED - 2X VOLUME
LINCOLN:
2009 MKS, MKZ, Navigator
This article supersedes TSB 9-1-5 to update the Issue statement and Service Procedure.
ISSUE
Some 2009 MKS, MKZ and Navigator vehicles equipped with the THX audio system may experience a popping, screeching, feedback condition, or a no audio issue when starting the vehicle after a cold soak. Vehicles equipped with the THX audio system and not equipped with navigation may also experience the THX setting defaulting back to the stereo setting or the volume coming on at a higher level after a key cycle.
ACTION
Follow the Service Procedure steps to correct the condition.
SERVICE PROCEDURE
NOTE
FOR NON-NAVIGATION VEHICLES WITH THE THX SETTING DEFAULTING TO STEREO AFTER A KEY CYCLE, REPROGRAM THE THX AUDIO DIGITAL SIGNAL PROCESSOR (DSP) MODULE PER STEP 2.
For vehicles with the popping noise/feedback issue:
1. Verify that the feedback noise is gone within 10 seconds of starting the vehicle, or that the audio issue is not resolved after letting the vehicle run for at least 30 seconds then restarting the vehicle.
a. If the noise is gone after 10 seconds and audio sound is restored, proceed to Step 2.
b. If the noise is not gone or the audio sound does not return, continue with normal Workshop Manual diagnostics.
2. Reprogram the THX audio DSP module to the latest calibration using IDS release 59.7 Patch 10 and higher or 60.1 Patch 1 and higher. This new calibration is not included in the VCM 2009.3 DVD. Calibration files may also be obtained at the website.
WARRANTY STATUS: Eligible Under Provisions Of New Vehicle Limited Warranty Coverage
IMPORTANT: Warranty coverage limits/policies are not altered by a TSB. Warranty coverage limits are determined by the identified causal part.
OPERATION DESCRIPTION TIME
090509A 2009 MKS, MKZ, 0.3 Hr.
Navigator: Reprogram The
DSP Module (Do Not Use
With 12650D, 12651D,
12651D4)
DEALER CODING
CONDITION
BASIC PART NO. CODE
18B849 04
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