Contents: Removal ↡ Installation ↡
Warning: The central assembly contains parts that are sensitive to the level of static electricity that accumulates on human skin. When the harness connector is disconnected, the free contacts can easily conduct static electricity to these parts, causing them to fail or even be damaged. The damage may not be noticeable and may not be immediately apparent. Costly repairs can be avoided by following these basic rules:
- a) Hold the ECU only by the housing: do not touch the unit contacts with your fingers or tools.
- b) When working on the ECU, ground yourself from time to time by touching metal objects, such as unpainted water pipes. This will allow the static electricity to drain from your body.
- c) Do not leave the ECU disconnected longer than necessary for operation.
Removal
1. Disconnect the negative battery terminal.
2. To access the connectors underneath the unit, remove the cover from underneath the instrument panel on the driver's side.
3. Disconnect all the plugs from the multi-pin connector on the rear bottom of the central mounting block. Each multi-pin plug is different in shape, so it can only be installed in the corresponding socket. However, we recommend that you label each plug.
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4. Remove the bolts securing the main ground bus to the engine compartment bulkhead behind the instrument panel. Record the location of each ground wire.
5. Working in the engine compartment, unscrew the screws and remove the additional relay holder.
6. Remove the cover from the fuses on the central mounting block.
7. Unscrew the two screws and two nuts securing the block to the engine compartment bulkhead.
8. Pull the unit forward and up, then unscrew the wire terminals and disconnect the plugs. Record their location as you remove them.
9. Remove the center mounting block from the engine compartment.
Installation
10. Installation is carried out in reverse order.