Diagnostic procedure

DTC P1621 - DIAGNOSTIC PROCEDURE

STEP	INSPECTION		ACTION
1	VERIFY RELATED REPAIR INFORMATION AVAILABILITY Check for related Service bulletins and/or on-line repair information availability. Is any repair information available?	Yes	Perform repair or diagnosis according to the available repair information. If the vehicle is not repaired, go to the next step.
1		No	Go to the next step.
2	VERIFY DTC P1621 DETECTED AGAIN Clear the DTC from the memory using the WDS or equivalent. Turn key to OFF, then start engine. Is same DTC present?	Yes	Perform code word reprogram procedure. (See IMMOBILIZER SYSTEM REPROGRAM PROCEDURE [CALIFORNIA EMISSION REGULATION APPLICABLE MODELS] .) (See IMMOBILIZER SYSTEM REPROGRAM PROCEDURE [FEDERAL EMISSION REGULATION APPLICABLE MODELS] .)
2		No	Go to the next step.
3	VERIFY TROUBLESHOOTING OF DTC P1621 COMPLETED Clear the DTC from the memory using the WDS or equivalent. Turn key to OFF, then start engine. Is same DTC present?	Yes	Replace PCM, then go to the next step.
3		No	Go to the next step.
4	VERIFY AFTER REPAIR PROCEDURE Perform the "After Repair Procedure". (See AFTER REPAIR PROCEDURE .) Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE .)
4		No	Troubleshooting completed.