FUEL INJECTOR ELECTRICAL DAMAGE INFORMATION

VEHICLES AFFECTED: All Cadillac

DFI/EFI fuel injectors may be permanently damaged when subjected to abnormal current loads during diagnosis. while the ECM will not allow enough current to damage the injector during vehicle operation, full battery voltage must not be applied across injector terminals for diagnosis. Full battery voltage applied across the injector will destroy the solenoid coil within half a second.

To aid in diagnosis of injector system operation, an injector harness tester such as one available from Burroughs Tool & Equipment Corporation as tool number BT8320 can be used to differentiate between an electrical or fuel system condition. However, its use should not entirely supersede the diagnostic procedures recommended in the 1983 Product Service Bulletin 6-146 and the appropriate Service Information Manuals. This tool is a substitute for an unpowered test light. The primary benefit of this tool is that it can be directly plugged into the injector harness to allow diagnosis without the assistance of a second person to crank the engine.

The tool information, while obtained from a source believed to be reliable, is being forwarded as a matter of information only. There may be additional manufacturers of such equipment. GM Canada does not endorse, indicate any preference for, or assume any responsibility with respect to the products, equipment, or services mentioned therein or for any other such item which may be available from other sources.

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.