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Obdii Circuit Repairs

Repairs for On-Board Diagnostics II (OBDII) emission control circuits follow the procedures. When servicing OBDII circuits, the following guidelines are also essential:
^ Do not move or alter grounds from their manufactured locations.
^ Do not tie aftermarket accessories into OBDII circuits.
^ Only repair OBDII circuits in accordance with the manufactured configuration.
^ Always replace a relay in an OBDII circuit the same replacement part. Damaged relays should be discarded, not repaired.
^ Refer to Fuse Block Details to identify OBDII circuit fusing. Power and Ground Distribution
^ Make sure that Connector Position Assurance (CPA) locks and Terminal Position Assurance (TPA) locks are reinstalled on connectors that use them.
^ After repair of connectors or connector terminals, make sure to achieve proper terminal retention. Refer to Repairing Connectors for procedures. Repairing Connectors
^ Before repairing OBDII heated oxygen sensors and related wiring, always review the special repair guidelines.
^ When installing an electrical ground fastener, be sure to apply the specified torque. Ground torque specifications are listed in Ground Distribution. Power and Ground Distribution
^ After repair of connectors, make sure to reinstall connector seals, where used. Inspect seals for wear and damage. Replace worn or damaged seals.