2003 Ski-Doo ZX Series Factory Shop Manual, Page 97Get this manual
Section 03 TROUBLESHOOTING Subsection 05 (ELECTRICAL SYSTEM)
SYMPTOM CONDITION TESTINSPECTION
RER (ROTAX ELECTRONIC REVERSE) DOES NOT WORKNORMAL USE1Check idle speedaWrong idle speedAdjust according to specification (refer to TECHNICAL DATA)2Check spark plugaFaulty spark plugReplace3Check drive belt heightaWrong belt heightAdjust according to specification (refer to DRIVE BELT)4Check carburetor synchronization and air screw adjustmentaWrong adjustmentAdjust according to specification (refer to TECHNICAL DATA) and read carburetor subsection5Check electrical connectionsaBad electrical connections or damaged wiresClean or replace6Check MPEMaFaulty MPEMReplace