Control Unit

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NOTE: Control units are known to be the cause of various customer DRIVEABILITY complaints. Various campaigns which may include control unit replacement, and system modifications have been implemented by Volkswagen to remedy this situation. Always refer to TECHNICAL SERVICE BULLETINS for the latest information concerning DRIVING PERFORMANCE.

If a problem is not remedied after completing the test procedures in ON-BOARD DIAGNOSIS, and SYSTEM ELECTRICAL TESTS, the control unit may be found to be defective. Replace the control unit with a known good unit and retest as necessary.

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