Tachometer Inaccurate

Turn ignition switch to ON position. Connect scan tool to Data Link Connector (DLC). See COMPONENT LOCATIONS  . Select IPC DATA MENU on scan tool display. Start engine. If scan tool indicates engine RPM to be same as RPM on tachometer, repair as necessary. See procedures in TESTS W/CODES article in ENGINE PERFORMANCE section. If scan tool does not indicate engine RPM to be same as RPM on tachometer, replace IPC. See INSTRUMENT PANEL CLUSTER  under REMOVAL & INSTALLATION. Recheck system operation.