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Component Tests and General Diagnostics


Special Passkey Ignition Key - With Specific Resistance Coded Pellet:




Key Resistance Chart:







INCORRECT RESISTANCE MEASUREMENT

If an incorrect resistance measurement at the key contacts is suspected, check to see if:
1. Does it happen with only one key and not the others. If so, replace the faulty key.
2. Is the condition present with all the keys. If so, the lock cylinder is dirty or defective or there is a fault in the key resistance circuit wiring, connection, or contacts.


To check the key resistance circuit with an ohmmeter, perform the following procedure:
1. Measure the resistance across the key contacts while the key is removed from the vehicle. Measure across both side of the key at the key pellet.
2. Disconnect the PASS-Key decoder module, insert key into the ignition, and measure the resistance across lock cylinder circuit terminals of the decoder module harness connector. (Refer to schematics for terminal identification). Be sure to manipulate the harness while performing the test.
^ Resistance should be within 10 ohms of the resistance measured on the key when it was removed from the vehicle.
^ If resistance is NOT within 10 ohms, determine if the cause for the difference is the wiring, connections, dirty key/lock cylinder contacts, or a defective lock cylinder.
3. While rotating the key through all positions in the lock cylinder, monitor the resistance change across terminals of the circuit for the key pellet of the decoder module harness.
^ A change greater than 10 ohms indicates a problem with the lock cylinder or key contacts.