GM Service Manual Online
For 1990-2009 cars only

AM RADIO NOISE (REPLACE ICM)

SUBJECT: AM RADIO NOISE (REPLACE IGNITION CONTROL MODULE)

MODELS: 1993-1994 CADILLAC ELDORADO 1993-1994 CADILLAC SEVILLE 1994 CADILLAC CONCOURS 1993 CADILLAC ALLANTE EQUIPPED WITH 4.6L NORTHSTAR ENGINE (RPOS LD8 AND L37; VINS Y AND 9)

CONDITION:

SOME OWNERS MAY EXPERIENCE "STATIC" NOISE DURING THE OPERATION OF THEIR VEHICLE, WHILE THE RADIO IS IN USE, IN THE AM RADIO BAND.

CAUSE:

THIS CONDITION MAY BE CAUSED BY ELECTRO MAGNETIC INTERFERENCE EMITTED FROM THE IGNITION CONTROL MODULE.

CORRECTION:

TO REPAIR THIS CONDITION, REPLACE THE IGNITION CONTROL MODULE WITH A NEW CAPACITOR EQUIPPED **IGNITION CONTROL MODULE P/N 10477276, ICM BRACKET P/N 10472128, BOLT P/N 11516186 AND GROUND STRAP P/N 12164812.** THE GROUND STRAP WILL BE INSTALLED BETWEEN THE IGNITION CONTROL MODULE AND THE ENGINE BLOCK, USING THE FOLLOWING PROCEDURE:

**NOTICE:** THE NEW CAPACITOR EQUIPPED DIS MODULE, BRACKET, BOLT AND GROUND STRAP MUST BE USED TOGETHER TO CORRECT THE "AM RADIO NOISE CONDITION." IF THESE COMPONENTS ARE NOT USED SIMULTANEOUSLY, THE "AM RADIO NOISE" WILL STILL BE PRESENT AND POSSIBLY AMPLIFIED.

FOR IDENTIFICATION PURPOSES, THE NEW DIS MODULE BRACKET USED TO CORRECT THIS CONDITION IS SILVER IN COLOR AND REQUIRES THE USE OF THE NEW GROUND STRAP. THE PREVIOUS DIS MODULE BRACKET IS BLACK IN COLOR AND MUST NOT BE USED WITH THE GROUND STRAP. THE ABOVE MENTIONED COMPONENTS WENT INTO PRODUCTION AT THE HAMTRAMCK ASSEMBLY PLANT 2/4/94.

**REMOVE OR DISCONNECT** (FIGURE 1) ------------------------ 1. SPARK PLUG WIRES AT IGNITION CONTROL MODULE ASSEMBLY. 2. FOUR ELECTRICAL CONNECTORS AT IGNITION CONTROL MODULE. 3. FOUR BOLTS RETAINING ICM ASSEMBLY TO REAR CAMSHAFT COVER. 4. ICM ASSEMBLY FROM VEHICLE. 5. IGNITION COILS FROM ICM ASSEMBLY. 6. ICM FROM ASSEMBLY BRACKET.

**INSTALL OR CONNECT** (FIGURE 1) ---------------------- 1. ICM TO NEW ASSEMBLY BRACKET. 2. IGNITION COILS TO ICM ASSEMBLY. 3. POSITION "NEW" ICM ASSEMBLY ON REAR CAMSHAFT COVER AND HAND START NUMBER 1, 2, AND 3 BOLTS. 4. HAND START REMAINING BOLT #4 AS SHOWN IN FIGURE 1 THROUGH EYELET IN GROUND STRAP.

**TIGHTEN** ----------- FOUR BOLTS TO 12 N.M (106 LB. IN.).

5. FOUR ELECTRICAL CONNECTORS AT ICM. 6. SPARK PLUG WIRES AT ICM ASSEMBLY. 7. ATTACH BOLT THROUGH REMAINING END OF GROUND STRAP AND INSTALL IN RIGHT BANK CYLINDER HEAD (FIGURE 1). 8. TORQUE BOLT TO 11 N.M (97 LB. IN.).

SERVICE PARTS INFORMATION: REFER TO THE FOLLOWING PART NUMBERS WHEN ORDERING PARTS FOR THE AM RADIO NOISE CONDITION.

DESCRIPTION PART NUMBER ----------- ----------- IGNITION CONTROL MODULE 10477276 ICM BRACKET 10472128 BOLT 11516186 GROUND STRAP 12164812

NOTE: WHENEVER REPLACEMENT OF THE IGNITION CONTROL MODULE IS NECESSARY ON A 1993 TO 1994 NORTHSTAR ENGINE, THE ENTIRE AM RADIO NOISE PACKAGE MUST BE USED.

PARTS ARE EXPECTED TO BE AVAILABLE ON MARCH 7, 1994.

WARRANTY INFORMATION:

LABOR OPERATION LABOR TIME --------------- ---------- T 3455 0.4 HOUR

FIGURES: 2


Object Number: 84102  Size: FS

GENERAL MOTORS BULLETINS ARE INTENDED FOR USE BY PROFESSIONAL TECHNICIANS, NOT A "DO-IT-YOURSELFER." THEY ARE WRITTEN TO INFORM THOSE TECHNICIANS OF CONDITIONS OCCURRING ON SOME VEHICLES, OR TO PROVIDE INFORMATION THAT COULD ASSIST IN THE PROPER SERVICE OF A VEHICLE. PROPERLY TRAINED TECHNICIANS HAVE THE EQUIPMENT, TOOLS, SAFETY INSTRUCTIONS AND KNOW-HOW TO DO A JOB PROPERLY AND SAFELY. IF A CONDITION IS DESCRIBED, DO NOT ASSUME THE BULLETIN APPLIES TO YOUR VEHICLE, OR THAT YOUR VEHICLE WILL HAVE THAT CONDITION. SEE A GENERAL MOTORS DEALER SERVICING YOUR BRAND OF GENERAL MOTORS VEHICLE FOR INFORMATION ON WHETHER YOUR VEHICLE MAY BENEFIT FROM THE INFORMATION.

COPYRIGHT 1994. GENERAL MOTORS CORPORATION. ALL RIGHTS RESERVED.