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HOMESERVICE MANUALSMERCURY1991TRACER BASE, 4D SEDAN, AUTOMATICREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 13 (ENGINE CONTROLS - TESTS W/CODES - EEC 1.8L)CIRCUIT TESTSCIRCUIT TEST PGC - POWER & GROUND CHECK
1991 Mercury Tracer Base, 4D Sedan, Automatic

Circuit Test PGC - Power & Ground Check

1991 Mercury Tracer Base, 4D Sedan, AutomaticSECTION Circuit Test PGC - Power & Ground Check
WARNING: This page is about a different car, the 1994 Mercury Tracer and 1994 Ford Escort. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Enter this test only when directed here by CIRCUIT TEST STO or by another test. This test is intended to diagnose Keep Alive Power (KAPWR) and Ground (GND) circuits.
CIRCUIT PIN IDENTIFICATION

Circuit Breakout Box Pin No. PCM Pin Wire Color
A/T
GND 40 & 60 3A Black/Orange
GND 20 3B Black/Orange
GND 49 3C Black/Lt. Green
KAPWR 1 1A Blue/Red
M/T
GND 39, 40, 44 & 60 2A Black/Orange
GND 20 2B Black/Orange
GND 16 2C Black/Green
KAPWR 1 1A Blue/Red

1) Check System Integrity  Visually check all wiring, connectors and components for evidence of damage, shorting or looseness. If fault is found, repair as necessary. If no fault is found, go to next step.

2) Check Voltage  Turn ignition off. Install breakout box, leaving PCM disconnected. Measure voltage at KAPWR test pin at breakout box. If reading is about battery voltage, go to next step. If reading is less than battery voltage, repair wire as necessary.

3) Check Grounds  Ensure ignition is off, breakout box is installed and PCM is disconnected. Measure resistance between ground and GND test pin at breakout box. Repeat test for each ground wire. If resistance is less than 5 ohms, replace PCM. If resistance is 5 ohms or more, repair open ground wire.

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

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  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.