DVOM Compatibility

Important 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 the 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.


DVOM Compatibility Test
- Using a known good Low data Rate (EI) vehicle, install the diagnostic harness, connect the EEC Breakout Box to the EI diagnostic harness.

- Start the vehicle and measure the AC voltage between J18 (RC1I) and ground.

- The battery should be charaged and the engine must be idling between 700 and 800 rpm. The value should be between 1.0 and 2.0 volts (1.5 volts AC is typical).

NOTE: If you have the EI hand held testers, they may be used instead of the EI Diagnostic Harness/EEC Breakout Box to gain access to J18 (RC1D) and J31 Crankshaft Position Sensor (PIP) and Powertrain Control Module (PCM).

- Next, with the engine idling, measure between (PIP) and ground.

- This reading should be between 6.0 and 8.0 volts AC.

- CAUTION: 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.