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.
Before measuring voltage to check for electrical system,
check to make sure that battery voltage is 11V 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.
Loose connection of connector
Poor contact of terminal (due to dirt, corrosion or rust on it, poor
contact tension, entry of foreign object etc.)
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
for loose connection. Also check lock condition of connector if
equipped with connector lock.
1. Check for loose connection
Sensor
ECM
GENERAL INFORMATION
0A-7
SH410