Electrical Circuit Inspection Procedure; Open Circuit Check - Suzuki Swift User Manual

0A-12 GENERAL INFORMATION
Sensor
1. Check for loose connection
D When checking connection of terminals, check its male half
for bend and female half for excessive opening and both for
locking (looseness), corrosion, dust, etc.
D Before measuring voltage to check for electrical system,
check to make sure that battery voltage is 11 V or higher.
Such terminal voltage check at low battery voltage will lead
to erroneous diagnosis.
ELECTRICAL CIRCUIT INSPECTION
PROCEDURE
While there are various electrical circuit inspection methods, de-
scribed here is a general method to check its open and short circuit
by using an ohmmeter and a voltmeter.

OPEN CIRCUIT CHECK

Possible causes for the open circuit are as follows. As the cause is
in the connector or terminal in many cases, they need to be checked
particularly carefully.
D Loose connection of connector.
D Poor contact of terminal (due to dirt, corrosion or rust on it, poor
contact tension, entry of foreign object etc.).
D Wire harness being open.
When checking system circuits including an electronic control unit
such as ECM, TCM, ABS control module, etc., it is important to per-
form careful check, starting with items which are easier to check.
1) Disconnect negative cable from battery.
2) Check each connector at both ends of the circuit being checked
ECM
for loose connection. Also check lock condition of connector if
equipped with connector lock.