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ECM - Fed Emission Spec Change DTC (P0129)

Group: ENGINE ELECTRICAL

Number: 99-36-006

Date: APRIL, 1999

Model: 1999 2.4L SONATA FED SPEC

Subject
1999 2.4L SONATA ECM (FEDERAL EMISSION SPECIFICATION) CHANGE FOR DTC P0139

DESCRIPTION:

If a vehicle sets a Check Engine Light with diagnostic code (DTC) P0139 (Rear Oxygen Sensor Slow Response) and the vehicle meets the following specifications:

^ 1999 Sonata
^ 2.4L I4 Engine
^ Federal Emission Specification (See underhood label)
^ Produced before 3/09/99

then the likely cause is an engine control module (ECM) programming condition not the rear oxygen sensor.

If the vehicle meets the above criteria and the scan tool shows normal rear O2 activity, replace the ECM to correct the condition (refer to TSB # 99-36-005 for detailed Removal & Replacement instructions).





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INTERCHANGEABILITY: A





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