Pinpoint Tests BB: Transmission Control Module (TCM) Power Relay: 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 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.

WARNING: STOP THIS TEST AT THE FIRST SIGN OF A FUEL LEAK AND REPAIR AS REQUIRED. NO OPEN FLAME. NO SMOKING DURING FUEL DELIVERY CHECKS. FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT IN PERSONAL INJURY.

This pinpoint test is intended to diagnose the following:

harness circuits: B+, ISP-R, TCMRC and VPWR
TCM power relay (12A646)
TCM (7B012)

Fig 1: Identifying TCM Power Relay Connector

Courtesy of FORD MOTOR CO.

Pin	Circuit
5	VPWR (Vehicle Power)
2	TCMRC (Transmission Control Module Relay Control)
1, 3	B+ (Battery Positive Voltage)

Fig 2: Identifying Battery Junction Box-B (BJB-B) Connector

Courtesy of FORD MOTOR CO.

Pin	Circuit
46	VPWR (Vehicle Power)
39	TCMRC (Transmission Control Module Relay Control)

Fig 3: Identifying Transmission Control Module-A (TCM-A) Connector

Courtesy of FORD MOTOR CO.

Pin	Circuit
29	VPWR (Vehicle Power)
10, 9	VPWR (Vehicle Power)
40	TCMRC (Transmission Control Module Relay Control)
6	B+ (Battery Positive Voltage)