SERVICE MANUAL UPDATE SEC. 6E3 REVISED PCM TROUBLE CODE 47

SUBJECT: REVISED PCM TROUBLE CODE 47

MODEL/YEARS: 1992 TORONADO/TROFEO

The 1992 Toronado/Trofeo Service Manuals do not include PCM Code 47. Following are diagnostics for "PCM Code 47, BCM - PCM data circuit problem". When diagnosing a Code 47, refer to this bulletin and "Computer System Diagnosis" (SECTION 8D) in the service manual.

6E3-A-3800 (VIN L) DRIVEABILITY AND EMISSIONS CODE47 PCM-BCM DATA 3800 (VIN L) (TPI)

Check for momentary loss of BCM power (CKT 640) or ground (CKT 803), ignition "OFF" input (CKT 343), IPC wake-up (CKT555) or ground (CKT803). Reference "SELF-DIAGNOSTIC SYSTEM CHECK" charts in computer system diagnosis (Section 8D). Also, ensure that MEMCAL is properly installed and fully seated, ALDL cover jumper pins are intact, and ALDL cover is properly installed.

If code is set along with any of the following history codes: B322, B333, B334, B335, B336, B337, and B552, see BCM trouble code diagnosis (Section 8D2).

In addition, the following information updates the PCM Diagnostic Codes table on page 6E3-A-16.

PCM DIAGNOSTIC CODES

CODE DESCRIPTION ILLUMINATE SES ---- ----------- -------------- 47 PCM-BCM Data Circuit No

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.