Toyota Celica 1993 AT200 series Repair Manual page 740

BE.7
BODY ELECTRICAL SYSTEM _ GENERAL INFORMATION
T o l g n i t l o n S w i t c h
l G T e r m i n a l
O h m m e t e r
SW
.7
7 t )
- o -
O h m m e l e r
O h m m e l e r
V O L T A G E C H E C K
Establish conditions in which voltage is present at tho
check point.
Exa m ple:
@ - l g n i t i o n S W O N
@ - l g n i t i o n S W a n d S W 1 o n
@- lgnition SW, SW I and Relay on (SW 2 off)
Using a voltmater, connect ths negative (-) lead to a
good ground point or negativs (-) battery torminal
and the positive (+) lead to the connector or compo-
n o n t t e r m i n a l . T h i s c h e c k c a n b e d o n e w i t h a t o s t b u l b
instead of a voltmeter.
C O N T I N U I T Y A N D R E S I S T A N C E
C H E C K
l a ,
(b)
(a) Disconnsct the battsry terminal or wire so 11'1616
;5 ns ffi
voltage between the check Points.
(b) Contact the 2 leads of an ohmmeter to each of the
ch6ck Doints.
lf the circuit has diodes, rovorse the 2 leads and check
a g a i n .
When contacting the negative (-) lead to tho diode
positive (+) side and ths positive (+) lsad to tho
negative (-) side, thsrs should be continuity. When
contacting the 2leads in reverse, thero should bo no
co ntin u ity.
HINT: Specifications may vary depending on the type
of tester, so rofer to the tostor's instruction manual
before performing the inspsction
C h e c k L E D ( L i g h t E m i t t i n g D i o d e ) i n t h o s a m € m a n n e r
as that for diodes.
H I N T :
.
Usa a testsr with a power source of 3 V or
greater to overcome the circuit resistance.
.
lf a suitable tester is not available, apply battsry
positive voltage and check that the LED lights up.