Audio System - AM Band Radio Interference
Article No.04-1-7
01/26/04
ENTERTAINMENT SYSTEM - AM RADIO
INTERFERENCE - VEHICLES PRODUCED PRIOR TO
12/01/2003
LINCOLN:
2003-2004 LS
ISSUE
Some Lincoln LS vehicles produced prior to 12/01/2003 may exhibit interference or popping/clicking noise on certain AM radio stations with the ignition on. The condition may be caused by interference created by the windshield wiper motor. The interference can occur with the windshield wipers on or off.
ACTION
To service, first verify the condition by disconnecting the windshield wiper motor C1026 (refer to Wiring Diagram Manual). If the condition is corrected, then perform the Service Procedure outlined in this TSB. If the condition is not corrected by disconnecting C1026, then compare to a like vehicle, as this may be a normal vehicle characteristic resulting from a weak radio station signal. If the condition is not corrected by disconnecting C1026, and is not comparable to a like vehicle, then refer to Workshop Manual Section 415-00 for diagnostics.
NOTE
POOR AM RECEPTION/PERFORMANCE MAY BE CAUSED BY AFTERMARKET TINTING OF THE BACK GLASS. MANY AFTERMARKET TINTING PRODUCTS ARE A METALLIC COMPOSITE MATERIAL CAUSING THE ANTENNA TO SHORT OUT TO THE DEFROSTER GRID. DO NOT PERFORM THIS TSB IF THE VEHICLE IS EQUIPPED WITH AFTERMARKET TINTING ON THE BACK GLASS.
NOTE
CELLULAR PHONE ANTENNA BASES INSTALLED OVER THE ANTENNA GRID ON THE BACK GLASS CAN AFFECT AM RADIO RECEPTION/PERFORMANCE. DO NOT PERFORM THIS TSB IF THERE IS A CELLULAR PHONE ANTENNA BASE INSTALLED OVER THE ANTENNA GRID.
SERVICE PROCEDURE
VEHICLES WITHOUT RAIN SENSE WIPERS
1. Remove the passenger (right) side quarter trim panel to gain access to the 14334 wire harness (Figure 1). Refer to Workshop Manual Section 501-01.
NOTE
DO NOT REMOVE THE SAFETY BELT ANCHOR BOLT. THE QUARTER TRIM PANEL ONLY NEEDS TO BE MOVED TO GAIN ACCESS TO THE 14334 WIRE HARNESS.
2. Locate C312 for vehicles WITHOUT Side Air Curtains or C3049 for vehicles WITH Side Air Curtains (Figure 1).
3. Locate circuit 8-KA41 (WH/GN wire), which is located at Pin 8 of C312 or Pin 4 of C3049. Refer to the Wiring Diagram Manual for system schematic and connector information.
4. Disable circuit 8-KA41 (WH/GN wire) by removing Pin 8 from C312 or Pin 4 from C3049 and taping back into the 14334 wire harness to prevent short circuits.
NOTE
CIRCUIT 8-KA41 (WH/GN WIRE) IS PRESENT ON ALL VEHICLES BUT IS NOT REQUIRED ON VEHICLES THAT ARE NOT EQUIPPED WITH RAIN SENSE WIPERS.
5. Install the passenger (right) side quarter trim panel. Refer to Workshop Manual, Section 501-01.
6. Verify the repair.
VEHICLES EQUIPPED WITH RAIN SENSE WIPERS
1. Remove the passenger (right) side quarter trim panel to gain access to the 14334 wire harness (Figure 1). Refer to Workshop Manual, Section 501-01.
NOTE
DO NOT REMOVE THE SAFETY BELT ANCHOR BOLT. THE QUARTER TRIM PANEL ONLY NEEDS TO BE MOVED TO GAIN ACCESS TO THE 14334 WIRE HARNESS.
2. Remove the 14334 wire harness pushpin fastener (closest to headliner) from the sheet metal (Figure 1).
3. Obtain a sheet of aluminum foil 21.6 cm x 27.9 cm (8.5 x 11 inches).
4. Fold the sheet of aluminum foil lengthwise to double the thickness.
5. Fold the sheet of aluminum foil lengthwise again to create a "V" or channel.
6. Place the aluminum foil over the 14334 wire harness (where it runs along the rear window) making sure the wire harness is in the channel (Figure 2).
NOTE
PULL THE REAR OF THE HEADLINER DOWN SLIGHTLY SO THAT THE ALUMINUM FOIL CAN BE WRAPPED AROUND THE 14334 WIRE HARNESS APPROXIMATELY 5.1 TO 7.6 CM (2 TO 3 INCHES) ABOVE THE HEADLINER.
7. Wrap the aluminum foil tightly around the 14334 wire harness (Figure 2).
NOTE
WRAPPING THE 14334 WIRE HARNESS WITH ALUMINUM FOIL NEAR THE TOP OF THE REAR WINDOW AND HEADLINER IS CRITICAL SO THAT THE WIRE HARNESS IS INSULATED FROM THE AM ANTENNA GRID IN THE REAR WINDOW (FIGURE 2).
NOTE
THE PUSH PIN FASTENER SHOULD BE WRAPPED IN ALUMINUM FOIL ALONG WITH THE 14334 WIRE HARNESS ALONG THE UPPER PORTION OF THE REAR WINDOW (FIGURE 2).
8. Install the 14334 wire harness pushpin fastener (closest to the headliner) into the sheet metal (Figure 1).
9. Create a shielded ground around the 14334 wire harness by grounding the aluminum foil to the sheet metal behind the quarter trim panel using a screw and washer assembly Part # N808720-S307 (Figure 2).
NOTE
USE A 1/8" DRILL BIT TO DRILL ONE (1) HOLE IN THE SHEET METAL BEHIND THE QUARTER TRIM PANEL SO THAT THE GROUND SCREW AND WASHER CAN BE INSTALLED.
CAUTION
CAUTION BE CAREFUL NOT TO RUN THE SCREW THROUGH THE WIRE HARNESS.
CAUTION
MAKE SURE THE SCREW IS NOT TOO LONG, WHICH COULD RESULT IN DAMAGE TO THE EXTERIOR BODY PANEL:
NOTE
INSTALL THE SCREW THROUGH THE ALUMINUM FOIL NEAR THE BOTTOM OF THE WRAPPED 14334 WIRE HARNESS (TOWARD THE PACKAGE TRAY) FOR THE BEST RESULTS (FIGURE 2).
10. Install the passenger (right) side quarter trim panel. Refer to Workshop Manual, Section 501-01.
11. Verify the repair.
Parts Block
OTHER APPLICABLE ARTICLES: NONE
WARRANTY STATUS: Eligible Under Provisions Of New Vehicle Limited Warranty Coverage
OPERATION DESCRIPTION TIME
040107A Verify Concern Perform 0.6 Hr.
Procedure For Vehicles
Without Rain Sense
Wipers: Includes Time To
Remove And Install
Quarter Trim Panel And
Verify Repair
040107B Verify Concern Perform 0.7 Hr.
Procedure For Vehicles
With Rain Sense Wipers:
includes Time To Remove
And Install Quarter Trim
Panel And Verify Repair
DEALER CODING
CONDITION
BASIC PART NO. CODE
14334 42
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