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Home >> Saturn >> 1994 >> SW2 Automatic >> Repair and Diagnosis >> Engine Performance >> Remove, Overhaul & Install >> Engine Controls - Remove/Install/Overhaul >> Ignition System >> Engine Control Module (ECM)/Powertrain Control Module (Pcm) >> Notes
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Engine Control Module (ECM)/Powertrain Control Module (Pcm): Notes

CAUTION: Electronic components used in control systems are designed to carry very low voltages. As little as a 30-volt charge created by static electricity can cause a total or degrading failure in ECM/PCM or other electronic components containing integrated circuits. Before servicing ECM/PCM, ground yourself and ground work area to discharge stored electricity.
STATIC CHARGE (VOLTS)

Movement Relative Humidity 10-20% Relative Humidity 65-90%
Handling Clear Plastic Bag 20,000 1200
Handling Vinyl Envelope 7000 600
Sliding On Velour Seat 15,000 400
Walking On Carpet 35,000 1500
Walking On Tile/Vinyl 12,000 50
CAUTION: DO NOT  remove part from packaging until ready to install. Ground any static-proof package before opening. DO NOT  touch electrical terminals of components unless properly grounded. DO NOT  lay electrical components on car seat, carpeting or dashboard. Use electrostatic protection mat and ground strap whenever possible. See Fig 1.
Fig 1: Servicing ECM/PCM Using 3M Anti-Static Mat
G54863Courtesy of GENERAL MOTORS CORP.
NOTE: Before replacing ECM/PCM, carefully inspect all wiring and control components. Failure to test for short circuits may result in repeated ECM/PCM failure due to grounds and Quad-Driver failure. To prevent internal damage to ECM/PCM, ensure ignition switch is in OFF position when disconnecting or reconnecting ECM/PCM connectors or 12-volt components.
NOTE: When replacing defective ECM/PCM, remove knock sensor module or PROM from defective ECM/PCM. New ECM/PCM does not come equipped with knock sensor module or PROM (if applicable). Install knock sensor module or PROM into new ECM/PCM.