CLARIFICATION ON (RWAL) TROUBLE CODES. GMC Truck Jimmy

SOME CONFUSION MAY EXIST ABOUT HOW TO READ THE TROUBLE CODES FOR THE RWAL SYSTEM ON THE MODELS LISTED ABOVE.

AFTER GROUNDING DIAGNOSTIC TERMINAL "H" TO "A", THE BRAKE LIGHT WILL BEGIN ITS FLASHING SEQUENCE.

IMPORTANT: THE BRAKE LIGHT MUST BE ON BEFORE GROUNDING "H" TO "A". IF THE BRAKE LIGHT IS NOT ON, AND TERMINAL "H" IS GROUNDED TO "A", YOU WILL INDUCE A FALSE CODE 9 IN THE SYSTEM.

THE FOLLOWING IS AN EXAMPLE OF HOW TO READ A CODE 4:

BEGIN THE COUNT WITH THE LONG FLASH. CONTINUE COUNTING THE NEXT THREE SHORT FLASHES. THE NEXT FLASH WILL BE A LONG FLASH WHICH STARTS THE SEQUENCE OVER AGAIN. THIS SEQUENCE WILL REPEAT AS LONG AS TERMINAL "H" IS GROUNDED TO "A".

IMPORTANT: SOMETIMES THE FIRST COUNT SEQUENCE WILL BE INCOMPLETE. HOWEVER, SUBSEQUENT COUNTS WILL BE ACCURATE.

EXAMPLE: CODE 4

********************************************************************* * FIRST LONG SHORT SHORT SHORT LONG SHORT * * FLASH FLASH FLASH FLASH FLASH FLASH * * * * 1 2 3 4 1 2 * * * * START END START * *********************************************************************

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