Powertrain Control Module (Pcm): Notes
CAUTION:
All vehicles are equipped with either an Engine Control Module (ECM), Powertrain Control Module (PCM) or Vehicle Control Module (VCM) for engine control. Unless specifically stated, references to PCM also apply to ECM and VCM equipped vehicles. Some vehicles equipped with an electronically- controlled transmission also use a Transmission Control Module (TCM) for transmission control. 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 PCM or other electronic components containing integrated circuits. Before servicing PCM, technician must ground himself and work area to discharge static electricity. See Fig 1.
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.
NOTE:
Before replacing PCM, carefully inspect all wiring and control components. Failure to test for short circuits may result in repeated PCM failure due to shorts and Quad-Driver failure. To prevent internal damage to PCM, ensure ignition switch is in OFF position when connecting or disconnecting PCM connectors or any electrical components.