IRREGULAR ELECTRONIC INSTRUMENT CLUSTER. Chevrolet Astro

REVISION: 04/07/94

THIS BULLETIN IS BEING REVISED TO ADD 1990-94 MODEL YEARS AND TO UPDATE SERVICE PARTS INFORMATION. PREVIOUS DIVISIONAL PUBLICATION NUMBERS WERE:

CHEVROLET 89-144-8C GMC TRUCK 89-T-53 GM CANADA 89-8-149 ----------------------------------------------------------------------

SUBJECT: IRREGULAR ELECTRONIC INSTRUMENT CLUSTER DISPLAY/FALSE TEMP INDICATION WHEN HORN IS ACTIVATED (REPLACE HORN ASSEMBLIES)

MODELS: 1989-94 CHEVROLET AND GMC TRUCK M/L VANS WITH ELECTRONIC INSTRUMENT CLUSTER (RPO U52)

CONDITION:

AN IRREGULAR ELECTRONIC INSTRUMENT CLUSTER DISPLAY CONDITION CAN SPORADICALLY OCCUR WHEN THE HORNS ARE ACTIVATED. WHEN THIS OCCURS, THE TEMPERATURE GAGE GOES FULL SCALE (HOT) AND RETURNS TO NORMAL OPERATION AFTER APPROXIMATELY TWO SECONDS, OR THE ELECTRONIC CLUSTER DISPLAY WILL DIM AND REMAIN DIM UNTIL THE IGNITION KEY IS TURNED OFF.

CAUSE:

UNSUPPRESSED ELECTRICAL SURGES FROM THE HORN CIRCUIT.

CORRECTION:

NEW HORN ASSEMBLIES WILL BE RELEASED INCORPORATING A SURGE SUPPRESSION CAPACITOR.

IF THIS CONDITION IS ENCOUNTERED, IT CAN BE REPAIRED BY INSTALLING THE ASSEMBLIES LISTED BELOW.

REMOVAL AND REPLACEMENT PROCEDURE: (REFER TO FIGURE 1.)

1. NOTE RADIO PRE-SET STATIONS.

2. DISCONNECT THE BATTERY GROUND CABLE FROM THE BATTERY.

3. DISCONNECT THE HORN LEAD CONNECTORS FROM EACH HORN ASSEMBLY.

4. REMOVE THE HORN RETAINING SCREWS.

5. REMOVE AND DISCARD THE HORN ASSEMBLIES.

6. INSTALL NEW HORN ASSEMBLIES P/N 10456444-RH "A" NOTE AND P/N 10456443-LH "F" NOTE USING RETAINING SCREWS PREVIOUSLY REMOVED. TORQUE SCREWS TO 14-20 N.M (10.32-14.75 LBS/FT).

7. RECONNECT THE HORN LEAD CONNECTORS TO THE HORNS.

8. RECONNECT THE BATTERY GROUND CABLE TO THE BATTERY.

9. RE-PROGRAM RADIO TO PRE-SET STATIONS AND SET TIME WHERE REQUIRED.

SERVICE PARTS INFORMATION:

P/N DESCRIPTION QUANTITY ------- ----------- -------- 10456443 HORN ASM.-LH ("F" NOTE) 1 10456444 HORN ASM.-RH ("A" NOTE) 1

PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.

WARRANTY INFORMATION:

FOR VEHICLES REPAIRED UNDER WARRANTY, USE:

LABOR OP DESCRIPTION LABOR TIME N0200 HORN ASSEMBLY, REPLACE USE PUBLISHED LABOR OPERATION TIME

FIGURES: 1

CAPTIONS: FIGURE 1 - HORN

Object Number: 85370 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 THAT MAY OCCUR 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 THAT 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.