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Home >> GMC >> 2003 >> Sierra 1500 HD, RWD >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 19 (Engine Controls - System & Component Testing - 6.6L) >> Computerized Engine Controls >> Engine Control Module & Fuel Injector Control Module >> Ground Circuits
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Ground Circuits

WARNING: This page is about a different variant/trim than selected.

Check ECM/FICM connectors for corroded or loose connections. Repair as necessary. Disconnect ECM/FICM connectors. Using a DVOM, measure resistance between negative battery terminal and ground terminals at ECM/FICM harness connector. If resistance is more than 5 ohms, repair open in affected ground circuit. If resistance is 5 ohms or less, ground circuits are okay.