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R-12 AIR CONDITIONING REFRIGERANT CAPACITY CALCULATION.

WHEN USING DISPOSABLE 14 FL. OZ. CANS OF R-12 AIR CONDITIONING REFRIGERANT TO RECHARGE A SYSTEM, THE FOLLOWING CONVERSION SHOULD BE USED TO DETERMINE THE AMOUNT REQUIRED: 14 FL. OZ. EQUALS 420 ML OR .88 LB.

WIRE WHEEL DISC CLIPS

TO AVOID REPLACEMENT OF WIRE WHEEL DISCS DUE TO BROKEN OR LOST SPRING CLIPS, THE CLIP, P/N 1620744, HAS BEEN RELEASED FOR SERVICE. THIS CLIP CAN BE USED ON ALL 1976-1981 C,E, AND K WIRE WHEEL DISCS AND IS TO BE RIVETED TO THE WHEEL DISC.

WAIT LIGHT/DIODE RELAY - 1981 DIESEL VEHICLES

THERE HAS BEEN CONFUSION RELATIVE TO WHAT APPEARS TO BE TWO (2) RELAYS ON THE COWL OF A 1981 DIESEL-EQUIPPED CADILLAC. LOOKING FROM THE FRONT OF THE CAR TOWARD THE COWL, THE UNIT ON THE RIGHT IS THE "WAIT" LIGHT RELAY. THIS RELAY HAS BEEN THE SAME SINCE 1978. SEE PAGE 63, FIGURE 1, FOR DEVILLE/BROUGHAM IN YOUR 1981 ELECTRICAL TROUBLESHOOTING MANUAL AND PAGE 71, FIGURE 1 FOR SEVILLE/ELDORADO. THE UNIT ON THE LEFT IS A DIODE MODULE. THIS IS SOMETIMES MISTAKEN FOR AN IDLE RELAY WHICH HAS BEEN DISCONTINUED.

THE DIODES IN THE DIODE MODULE ARE NOT NEW TO THE DIESEL CIRCUITRY. THEY WERE IN THE WIRING HARNESS ON PAST MODELS, BUT ARE NOW INCORPORATED INTO A MODULE TO IMPROVE SERVICEABILITY. THE MODEUL CONTAINS THREE (3) DIODES WHICH ARE PART OF THE CHARGING CIRCUIT AND GLOW PLUG CIRCUIT. THEY PREVENT UNWANTED CIRCUIT FEEDS WHICH CAN CAUSE A CUSTOMER COMMENT TO THE EFFECT THAT

- GENERATOR LIGHT WON'T GO OUT - CAR WON'T SHUT OFF WITH KEY

THE DIODE MODULE CAN BE TESTED BY USING A SELF POWERED TEST LIGHT AS FOLLOWS:

1. CONNECTING THE GROUND CLIP TO TERMINAL "C" AND TOUCHING THE OTHER PROBE TO TERMINALS "A", "B" AND "D". THE LIGHT SHOULD LIGHT AT EACH TERMINAL. IF NOT, THE MODULE IS DEFECTIVE AND SHOULD BE REPLACED.

2. REVERSE THE TEST LEADS AND PERFORM THE SAME TEST. THE LIGHT SHOULD NOT LIGHT. IF IT DOES, REPLACE THE MODULE.

WAIT LIGHT STAYING ON - 1981 DIESELS

IF A CONDITION IS ENCOUNTERED WHERE THE DIESEL WAIT LIGHT STAYS ON, THE WEATHER-PAK CONNECTOR LOCATED IN THE GLOW PLUG HARNESS SHOULD BE CHECKED FOR PROPER INSTALLATION, MAKING SURE THAT A POSITIVE CONNECTION HAS BEEN OBTAINED

THM TORQUE SPECIFICATION REVISION - THM 200 4-R

THE TORQUE SPECIFICATION LISTED ON PAGE 7D-70 IN THE 1981 CADILLAC SERVICE MANUAL FOR VALVE BODY TO CASE BOLTS IS INCORRECT. IT SHOULD BE 10-14 N M OR 7-10 FT. LBS.

INPUT SUN GEAR INSTALLATION THM 125

IN SERVICEMAN BULLETIN 81-57, INSTALLATION OF THE INPUT SUN GEAR WITHOUT AN IDENTIFICATION GROOVE WAS INCORRECTLY GIVEN AS "WITH THE CHAMFERED SIDE TOWARD THE INPUT DRUM HOUSING". THE GEAR WITHOUT A GROOVE SHOULD BE INSTALLED "WITH THE CHAMFERED SIDE UP AWAY FROM THE INPUT DRUM HOUSING."

SUNROOF SUNSHADE PANEL NOISE

RECENT REPORTS INDICATE SOME CASES OF A BUZZING SOUND FROM THE SUNSHADE WHEN THE ASTROROOF IS PARTIALLY OR FULLY OPEN. THIS CAN BE CAUSED BY THE CELLOPHANE SHIELD OVER THE MASTIC. TO CORRECT THIS BUSSING SOUND, REMOVE THE SUNSHADE FOR ACCESS TO THE MASTIC MATERIAL AND USE SCISSORS TO TRIM OFF THE EXCESS CELLOPHANE (ABOUT 1/8" TO 1/4") THAT EXTENDS PAST THE EDGE OF THE MASTIC. REINSTALL THE SUNSHADE.

MAP LAMP LENS RATTLE CORRECTION - 1980-81 C,E, AND K.

A RATTLING CONDITION AT THE MAP LIGHT AND SUNSHADE ROD RETAINER ASSEMBLY MAY EXIST ON SOME 1980-1981 CADILLACS (C,E, AND K BODIES). THIS CONDITION CAN BE CORRECTED BY REPLACING THE MAP LAMP LENSES WITH PART NO. 20325663 (LEFT SIDE) AND 20325662 (RIGHT SIDE). REFER TO SERVICEMAN BULLETIN NO. 80-76 (GROUP 10) FOR INSTRUCTIONS FOR REMOVAL AND INSTALLATION OF THE LENSES.

THE LENSES ARE SPECIFIC FOR THE RIGHT AND LEFT SIDE. THESE LENSES CANNOT BE REVERSED UNLESS FORCED, IN WHICH CASE THE RESULTS WOULD BE POOR LIGHT DISTRIBUTION AND POSSIBLY RATTLES. DO NOT REVERSE THE LENSES AS DESCRIBED IN SERVICEMAN BULLETIN 80-76 UNLESS IT CAN BE DETERMINED THAT THE LENSES WERE ORIGINALLY INSTALLED IN THE WRONG POSITIONS.

FOR WARRANTY PURPOSES, USE OPERATION NO. N1180 AT 0.2 HOUR.

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.