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Home >> GMC >> 1990 >> Forward Control 6.2 J, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - Diesel >> ECM Location >> Test Equipment
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Test Equipment

A tachometer, test light, Digital Volt/Ohmmeter (DVOM) with a minimum 10-megohm input impedance, a vacuum gauge, and jumper wires are required to test and diagnose DEC system. A "Scan" tester may also be used to access data parameters. Tester will supply a visual reading of most inputs to the ECM and some outputs.