Pinpoint Tests QA: Unable to Activate Self-Test/Network Communication Error: Introduction

WARNING: TO PREVENT THE RISK OF HIGH-VOLTAGE SHOCK, ALWAYS FOLLOW PRECISELY ALL WARNINGS AND SERVICE INSTRUCTIONS, INCLUDING INSTRUCTIONS TO DEPOWER THE SYSTEM. THE HIGH-VOLTAGE HYBRID SYSTEM UTILIZES APPROXIMATELY 300 VOLTS DC, PROVIDED THROUGH HIGH-VOLTAGE CABLES TO ITS COMPONENTS AND MODULES. THE HIGH-VOLTAGE CABLES AND WIRING ARE IDENTIFIED BY ORANGE HARNESS TAPE OR ORANGE WIRE COVERING. ALL HIGH-VOLTAGE COMPONENTS ARE MARKED WITH HIGH-VOLTAGE WARNING LABELS WITH A HIGH-VOLTAGE SYMBOL. FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT IN SERIOUS PERSONAL INJURY OR DEATH.

This pinpoint test is intended to diagnose the following:

unable to communicate with the powertrain control module (PCM)
unable to communicate with the transaxle control module (TCM)
incorrect self-test procedure
harness circuits: B+, ETCREF, GND, ISP-R, PWRGND and VPWR

Fig 1: Identifying Electronic Throttle Body (ETB) Connector
Courtesy of FORD MOTOR CO.

Fig 2: Identifying Transaxle Assembly-A Connector
Courtesy of FORD MOTOR CO.

Fig 3: Identifying Powertrain Control Module (PCM) Connector

Courtesy of FORD MOTOR CO.