Suzuki AN400 Service Manual page 11

Voltage check
If voltage is supplied to the circuit being checked, voltage
check can be used as circuit check.
1) With all connectors/couplers connected and voltage
applied to the circuit being checked, measure
voltage between each terminal and body ground.
2) If measurements were taken as shown in the figure
below and results are as listed in the following, it
means that the circuit is open between terminals "A"
and "B".
Voltage between
"A" and body ground: Approx. 5 V
"B" and body ground: Approx. 5 V
"C" and body ground: 0 V
3) Also, if measured values are as listed in the
following, a resistance (abnormality) exists which
causes the voltage drop in the circuit between
terminals "A" and "B".
Voltage between
"A" and body ground: Approx. 5 V
"B" and body ground: Approx. 5 V – 2 V voltage
drop
"C" and body ground: 3 V – 2 V voltage drop
0V
"A"
"A"
ECM
"B"
"C"
5V
5V
5V
"B" "C"
I705H1000007-01
Short circuit check (Wire harness to ground)
1) Disconnect the (–) cable from the battery.
2) Disconnect the connectors/couplers at both ends of
the circuit to be checked.
NOTE
If the circuit to be checked branches to other
parts as shown, disconnect all connectors/
couplers of those parts. Otherwise, diagnosis
will be misled.
3) Measure resistance between terminal at one end of
circuit ("A" terminal in figure) and body ground. If
continuity is indicated, there is a short circuit to
ground between terminals "A" and "C".
"A"
"A"
"D": To other parts
Precautions: 00-6
"D"
"B"
ECM
"C"
"E"
5V
"C"
I705H1000008-01
"E": Other parts