Toyota Corolla, MY09-10, 1.8L Unichip PnP Installation Instructions

The OEM and PnP Plugs have release tabs that must be pressed before rotating the locking levers. Failure to use the release tabs may result in plug damage. Connect and disconnect the PnP connectors several times to get a feel for how the plugs work. When rotating the OEM and PnP Plug locking levers, if the Plug is fully seated in the connector the locking mechanism will be correctly engaged and the plug will be drawn down into the connector. If the Plug is not fully seated, the locking mechanism will not be fully seated and although the locking lever rotates and feels like it locks, the locking mechanism will not be engaged and the plug will vibrate loose resulting in illumination of multiple dash lights.
1. Disconnect the car’s battery. Using a 10mm wrench, disconnect the cars battery at the negative terminal in the engine compartment.
2. Connect the PnP harness.
a. Locate the OEM ECU between the air box and the fuse box just behind the battery.
b. Remove the OEM plugs from the ECU.
c. Remove the protective plastic from one side of the kit provided long Velcro strip and position the Velcro on the large flat side of the PnP Harness Case.
d. Ensure the OEM fuse box cover is clear of dirt and grime.
e. Remove the remaining protective plastic strip from the Velcro strip on the bottom of the PnP case and position the PnP Case over the center of the OEM fuse box cover with the plugs and connectors facing the engine.
f. Press the PnP Harness Case firmly in place.
g. Connect the two OEM plugs into the PnP Harness Case Connectors and ensure they lock in place.
Note: The OEM wiring Plug loom is secured to the main wiring loom via a plastic connector which may need to be released to provide sufficient slack.
h. Connect the two PnP Harness Plugs into the OEM ECU connectors.

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