Electrical - Revised VSS/Ignition Diagrams

90pontiac20
Bulletin Number: 88-6-103
Reference Number: 016535
Publish Date: 9/90
Subject: SERVICE MANUAL UPDATE - SECTION 6E1 - TO CORRECT ECM MECHANIZATION

Models
Affected: 1984-88 BONNEVILLE AND FIREBIRD MODELS WITH 5.0L (VIN G/H), 5.7L (VIN 6)
This bulletin applies to 1984-1988 5.0L (VIN H/G) and 5.7L (VIN 6) Bonneville and Firebird Carline Service Manuals. In DRIVEABILITY AND EMISSIONS (SECTION 6E1) the ECM Wiring Diagrams may illustrate that the 439 (ignition feed) circuit is spliced to circuit 437 (vehicle speed sensor).

Ignition voltage is not supplied to, nor is circuit 439 spliced to the vehicle speed sensor circuit (437).