The Code 42 Diagnostic Chart is revised to clarify the correct procedure for measuring resistance at the ECM connector.
This Chart replaces the Code 42 Chart found in Section 6E3, "Driveability and Emissions", page 6E3-A-57, in the Firenza and Cutlass Calais Service Manual for the 1988 (VIN D) "N" engine applcations.
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.