4.5
USE OF DIGITAL VOLT-OHM METER
4.5.3
Voltage Measurements
Perform the following steps to measure voltage.
1. Connect the red test lead to the V-
connector and the black lead to the com input on the
meter. If a DC-AC switch is present, ensure it is switched to the DC position.
2. Set the function range/switch to the desired volts position. If the magnitude of the voltage
is not known, set the switch to a range that will be able to read most voltages seen on
a vehicle. Typically, a 20V range will do. Then, reduce the range until a satisfactory
reading is obtained.
3. Connect the test leads to the circuit being measured. In the DDEC system diagnostic
procedures, voltage measurements are always given as being taken at pins, sockets, battery
+, or ground. Following the voltage measurement point, the color test lead to be used
is given in parenthesis (red is the V-
connection, and black is the com connection).
Example: If the procedure displays, "Take voltage reading at socket A3 (red lead) to
socket C3 (black lead)", see Figure 4-1 for the hook-up.
1.Red Lead
2.Black Lead
Figure 4-1
Voltage Measurement Hook-up
All information subject to change without notice.
4-10
6SE497 9709 Copyright © 1997 DETROIT DIESEL CORPORATION
