Have Haynes Manual; about to take a stab at repair; do duplicate codes mean more than 1 problem in the system?
Why duplicate OBD-II codes in a failed emissions inspection report? on 2000 Ford Taurus
More than likely what you are seeing is a code that has 'set' and a 'pending' (PND) code which just means the problem is repeating itself (in simple terms). AND just as you stated the word 'system' is key. the codes often refer to the symptom and system it's affecting , not just a failed part.Understand why your replacing a part BEFORE you replace it , otherwise could lead to a lot of frustration and wasted money.Good luck.Reply on this post if you have questions.
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What is the code.
SCAN ALL CODES AND POST SO WE CAN ADV