SERVICE MANUAL UPDATE SEC.6E3 REVISED CODE 41 DIAG. CHART

SUBJECT: SERVICE MANUAL UPDATE-SECTION 6E3-DRIVEABILITY AND EMISSIONS REVISED CODE 41 DIAGNOSTIC CHART

MODELS AFFECTED: 1991 PARK AVENUE, RIVIERA AND REATTA MODELS EQUIPPED WITH 3800 (VIN L) ENGINE

This bulletin updates the Code 41 Diagnostic Chart in "Driveability And Emissions" Section 6E3 for 1991 Park Avenue and Riviera/Reatta models equipped with the 3800 (VIN L) engine. The revised chart addresses the possibility of a faulty ignition module causing Code 41 to be set by not supplying the CAM Sensor signal to the PCM. Separate charts are included with this bulletin for "Type I" and "Type II" ignition modules. To ensure proper diagnosis and to avoid replacement of good parts, the type of system being diagnosed must be identified and the correct chart for the applicable system used.

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.