DIESEL RUN ON CONDITION HIDDEN GENERATOR LIGHT

SHOULD A CONDITION EXIST IN WHICH A BUICK REGAL, EQUIPPED WITH A DIESEL ENGINE, CONTINUES TO RUN AFTER THE IGNITION IS TURNED OFF, CHECK THE FOLLOWING WIRING CIRCUIT. CHECK FOR A SOLID BROWN WIRE FROM THE 'HIDDEN GENERATOR LIGHT' CONNECTION TO THE 'N' TERMINAL OF THE 'DIESEL ELECTRONICS MODULE'. IF THIS WIRE IS PRESENT, CUT IT AND TAPE THE ENDS. LEAVE THE 2 BROWN/ WHITE STRIPED WIRES FROM THE 'HIDDEN GENERATOR LIGHT' CONNECTOR TO THE 'CHARGE INDICATOR' AND TO TERMINAL 'K' OF THE 'DIESEL ELECTRONICS MODULE' UNTOUCHED. (SEE FIGURE #1). IF THIS PROCEDURE DOES NOT CORRECT THE CONDITION, CHECK THE DIODE IN THE 'DIESEL ELECTRONICS MODULE' WITH AN OHMMETER. CONNECT THE OHMMETER LEADS ACROSS TERMINALS 'K' AND 'N' OF THE 'DIESEL ELECTRONICS MODULE' AND THEN REVERSE THE LEADS. A GOOD DIODE WILL SHOW A HIGHER RESISTANCE ONE WAY, AND A LOWER RESISTANCE WHEN THE LEADS ARE REVERSED . IF THE METER SHOWS INFINITE RESISTANCE, INDICATING AN OPEN, OR EVEN RESISTANCE BOTH WAYS, THE DIODE IS BAD. TO CORRECT THIS SITUATION , INSTALL A NEW DIODE IN SERIES WITH THE BROWN/WHITE WIRE (CIRCUIT 504 ) AT TERMINAL 'K' OF THE 'DIESEL ELECTRONICS MODULE.' (SEE FIGURE #2). DIODES MAY BE OBTAINED THROUGH LOCAL ELECTRONICS SUPPLY STORES. ASK FOR DIODES WITH INDUSTRIAL NUMBER OF 1N4003 OR EQUIVALENT, RATED 200 VOLTS AT 1 AMP. SERVICE PROCEDURE 1.DISCONNECT THE TWO (2) NEGATIVE BATTERY CABLES. 2.LOWER THE GLOVE DOOR AND COMPARTMENT OUT OF THE WAY. 3.UNCLIP 'DIESEL ELECTRONICS MODULE' AND BRING HARNESS OUT INTO OPEN AREA. 4.CUT AND TAPE BROWN WIRE. 5.IF CONDITION STILL PERSISTS, CHECK OUT DIODE. IF BAD, REPLACE BY CUTTING BROWN/WHITE WIRE AND SOLDERING DIODE IN SERIES AS SHOWN IN FIGURE #2. 6.REPLACE MODULE AND GLOVE BOX.

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.