Operating Instructions - Snap-on Equipment

General MaintenanceThe Optional RPM kit contains several unique vehicle probes to obtain RPM. RPMs,depending on the vehicle and its year, can be obtained from the following sources.SourceSpark Plug WireIgnition Coil PrimaryIgnition System NoiseOBD IIProbeInductive ProbeInductive ProbeRFI, Radio Frequency Probe1996 and Newer Vehicles through the OBDDiagnostic ConnectorEach method for reading RPM requires a different setup of the FGA softwarebefore RPM can be read. In addition only one RPM pickup can be used at a time.The connection of the RPM probes to the FGA was described in the assemblyinstructions provided with the RPM kit. As a quick review, the probes areconnected as follows:12' Yellow RPM Extender Cable connects to the Communications Panel of theFGA. Into this cable you can connect either the Inductive Probe or the RFI Probe.10' DB9 to DB9 communications cable connects to the RS232 OUT connectionon the FGA. Connect the OBD II diagnostic interface into the other end of the cable.Using The Inductive ProbeThe Inductive probe can be used to read ignition system high voltage, from a plugwire or ignition system primary voltage at the ignition coil. Reading engine RPMfrom a plug wire is the preferred, and in most cases the most reliable, enginespeed source.Pocket PC SetupTo setup the tachometer,1. Connect the inductive pickup to the number one spark plug wire and startthe engine.2. From the main menu select Meters or Automatic Tests, then selectTachometer.—The Tachometer screen displays.Figure 4-1: Tachometer Setup Screen4-4