How to Fix the Computer in a '92 Prelude
- 1). Disconnect the negative battery cable and set it aside, ensuring that it doesn't touch metal. Ground yourself by touching metal. Even a small static electricity shock could damage the ECU.
- 2). Pull the right side kick panel away from the wall. Pull the small carpet next to the console back, to gain access to the rest of the carpet. With these two pieces out of the way, you can pull back the rest of the carpet.
- 3). Remove the ECU cover, using the appropriate socket. Pull the ECU straight out toward you just enough to reach the connectors.
- 4). Remove the bolts that hold the connectors in place, using the appropriate socket. Pull the three connectors straight off the back of the ECU, taking care to not bend the pins.
- 5). Remove the cover on the back of the old and new ECUs. Pull the PROM, a square or rectangle computer chip, out of the old ECU and insert it into the new ECU. PROM stands for programmable read only memory. Reinstall the cover.
- 6). Slide the ECU into its cavity and push the wiring harness connectors onto the back, taking care to not bend the pins. Tighten the bolts snugly. Reinstall the floor cover, carpet and kick panel.
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