OBD II Circuit Repairs

A Repairs for On-Board Diagnostics II (OBD II) emission control circuits follow safety procedures. When servicing OBD II circuits, the following guidelines are also essential:
^ Do not move or alter grounds from their manufactured locations.
^ Do not connect aftermarket accessories into OBD II circuits.
^ Only repair OBD II circuits in accordance with the manufactured configuration.
^ Always replace a relay in an OBD II circuit with the same replacement part. Damaged relays should be discarded, not repaired.
^ Identify OBD II circuit fusing.
^ Make sure that CPA (Connector Position Assurance) locks and TPA (Terminal Position Assurance) locks are reinstalled on connectors that use them.
^ After repair of connectors or connector terminals, make sure to achieve proper terminal retention.
^ Before repairing OBD II 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.
^ After repair of connectors, make sure to reinstall connector seals, where used. Inspect seals for wear and damage. Replace worn or damaged seals.