PINPOINT TEST B: Powertrain Control Module (PCM) Power Relay: Introduction

1999 Ford Mustang GT, 2D Convertible, StandardSECTION Introduction
WARNING: This page does not describe the selected car, but rather 31 other vehicles, including the 2008 Mercury Sable, 2008 Mercury Mountaineer, 2008 Mercury Milan, 2008 Mercury Mariner, and 2008 Mercury Grand Marquis. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: The IGN START/RUN and ground circuits, or the B+ and VPWR circuits may be reversed in the harness connector. Refer to the Wiring Diagrams article Electronic Engine Control for schematic and connector information.

This pinpoint test is intended to diagnose the following:

  • harness circuits: B+, IGN START/RUN, INJPWRM, ISP-R, PCMRC, VPWR and GND
  • PCM power relay (12A646)
  • PCM (12A650)
Fig 1: Injector (INJ) Connector
GF0001545Courtesy of FORD MOTOR CO.
Vehicle Connector Pin Circuit
Fusion 3.0L,
Milan 3.0L
A 1 VPWR
All other vehicles A 2 VPWR
Fig 2: Powertrain Control Module Power (PCM Power) Relay Connector - A
GF0001546Courtesy of FORD MOTOR CO.
RENDER: 1.0x

NO RELATED

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