Tachometer Circuit Test: I30

Using a voltmeter, backprobe terminal No. 3 (White/Green wire) at instrument cluster 14-pin harness connector M29. See Figure . Start engine. Observe voltmeter while changing engine RPM. If voltage is higher at higher RPM and lower at lower RPM, tachometer circuit is okay at this time. If voltage is not higher at higher RPM and lower at lower RPM, repair open and/or short to ground in White/Green wire. See WIRING DIAGRAMS  .