Toyota COMPUTER-CONTROLLED SYSTEM Training Manual page 172

Wt
SYMPTOM SIMULATIO N
VIBRATION METHOD
(cont'd) :
When vibration seems to be the major cause .
WIRE HARNES S
Gently wiggle the wire harness vertically an d
~ r
horizontally . Connector joints and places where wir e
harnesses pass through the body are the major area s
to be checked .
Gently wiggl e
Gently tap
PARTS AND SENSORS
Gently tap the part or sensor in question with you r
finger .
NOTE R b h l i : emem er t at app y ng too much shock to a
J~~ JJ l
relay may cause it to open, making it appear that it i s
the relay that is at fault when there is really nothin g
wrong with it at all .
::2]
HEAT
METHOD
: When the malfunction seems to occur when the suspec t
area is heated .
Using a hair dryer, heat the component that is th e
likely cause of the malfunction .
Malfunc -
tions
NOTICE :
D h ° C
•
o not eat any component to more than 60
(140°F) ( temperature limit at which the componen t
can be safely touched with the hand) .
• Never open an ECU and apply heat directly to th e
pa
rt
s inside it .
3 WATER SPRAY METHOD
: When the malfunction seems to occur on a rainy
day or under conditions of high humidity .
Change the temperature and ambient humidity b y
spraying water onto the vehicle .
NOTICE :
• Never spray water directly into the engin e
compartment; spray it onto the front of the radiato r
through the grill .
• Never let water come in direct contact wit h
electronic components .
NOTE :
• If a vehicle is subject to water leakage, the leakin g
water may get into an ECU . When testing a vehicl e
with a water leakage problem, special caution mus t
be used .
164