FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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DVOM Compatibility Check

EQUIPMENT NOTE: Most DVOM's used by auto technicians belong to a class or type known as "averaging". Examples are the Rotunda Digital Volt-Ohmmeter 007-00001, Fluke 70, 20 series and Fluke 88. Recently technicians have started to use DVOM'S of a different class (True RMS, DVOM's, Fluke 87, 8060A, 8062A, etc.). True RMS DVOM's should not be used with the Pinpoint Tests because they may display different voltage readings depending upon if the DVOM is turned on first and then the test leads are connected, or if the leads are connected first and then DVOM is turned on. Also they may not auto range to the same range every time and some display significantly different values depending on the range selected. It would be impossible to list all of the meters and how to use each, so we are requesting that you perform the following test to verify your DVOM is compatible with the Pinpoint Tests.

Test Procedure

NOTE: The battery should be charged and the engine must be idling between 700 and 900 rpm.

1. Using a known good EI vehicle, install the EI (Low Data Rate) DIS or EI (High Data Rate) EDIS diagnostic cable.
2. Connect the EEC Breakout Box to the diagnostic cable.
3. Start the vehicle and measure the AC voltage between J53 (C1I) and ground. The value should be between 2 to 7 volts AC (4.5 volts AC is typical).

NOTE: If you have the EI (Low Data Rate) hand held testers they may be used instead of the Diagnostic Cable/EEC Breakout Box to gain access to J53 (C1I) and J43 (PIP I).

4. With the engine idling, measure between PIP and ground. This reading should be between 6 and 8 volts AC.

Test Result
If the readings you get agree with our test, your DVOM is OK to use with the Ignition Pinpoint Tests. If not, do not use it, it will lead to false parts replacement and the root cause will be difficult or impossible to find.