Toyota 1RZ, Supplement Manual

Page: 90 / 525

DI1HI--01
FI2547
-- DIAGNOSTICS ENGINE (1RZ--E)
DI--3
PRE--CHECK
1. DIAGNOSIS SYSTEM
(a) Description
The Engine ECU contains a built--in self--diagnosis sys-
tem by which troubles with the engine signal network are
detected and a check engine warning light in the com-
bination meter lights up.
By analyzing various signals as shown in the later table
(See page DI -- 15) the Engine ECU detects system ma l-
functions relating to the sensors or actuators.
In the normal mode, the self--diagnosis system monitors
14 items, indicated by code No.
as shown in DI -- 15. A
check engine warning light informs the driver that a mal-
function has been detected. The ECU stores the code(s)
until it is cleared by removing the EFI fuse with the ignition
switch off.
The diagnostic trouble code can be read by the number
of blinks of the check engine warning light when TE1 and
E1 terminals on the check connector are connected.
When 2 or more codes are indicated, the lowest number
(code) will appear first.
In the test mode, 10 items, indicated by code No. as
shown in
DI -- 15 are monitored. If a malfunction is de-
tected in any one of the systems indicated by code Nos.
13, 22, 24, 31, and 41 the ECU lights the check engine
warning light to warn the technician that malfunction has
been detected. In this case, TE2 and E1 terminals on the
check connector should be connected as shown later.
(See page DI --
5
) In the test mode, even if the malfunction
is corrected, the malfunction code is stored in the ECU
memory even when the ignition switch is off. This also ap-
plies in the normal mode. The diagnostic mode (normal
or test) and the output of the check engine warning light
can be selected by connecting the TE1, TE2, and E1 ter-
minals on the check connector, as shown later.
A test mode function has been added to the functions of
the self--diagnosis system of the normal mode for the pur-
pose of detecting malfunctions such as poor contact,
which are difficult to detect in the normal mode. This func-
tion fills up the self--diagnosis system. The test mode can
be implemented by the technician following the appropri-
ate procedures of check terminal connection and opera-
tion described later.
(See page DI --
5
)
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3RZ-F,3RZ-FE