Download DI-254

DI−254
DIAGNOSTICS
−
ABS & TRACTION CONTROL SYSTEM
DI1H0−06
DTC
C1203 / 53
ECM Communication Circuit
Malfunction
CIRCUIT DESCRIPTION
The circuit is used to send TRC control information from the ABS & TRC ECU to the engine and ECT ECU
(TRC+, TRC−), and engine control information from the engine and ECT ECU to the ABS & TRC ECU
(ENG+, ENG−).
DTC No.
DTC Detecting Condition
Trouble Area
C1203 / 53
Either of the following 1., 2. or 3. continues for 5 sec.:
1. When ECU terminal IG1 voltage is 9.5 V or more, the
condition that the data is not transmitted to engine and
ECT ECU continues for more than 5 sec.
2. When ECU terminal IG1 voltage is 9.5 V or more, engine
speed is 500 rpm or more and data receipt from engine
and ECT ECU is impossible.
3. The condition that the data sent from engine and ECT
ECU becomes repeatedly normal and abnormal occurs
10 times or more for 60 sec.
S TRC+ or TRC− circuit
S ENG+ or ENG− circuit
S Engine and ECT ECU
S ABS & TRC ECU
Fail safe function:
If any trouble occurs in the engine and ECT ECU communication circuit, the ECU prohibits TRC controls.
WIRING DIAGRAM
Engine and ECT ECU
ABS & TRC ECU
14
ENG+ E2
L
14
A22 ENG+
21
ENG− E2
P
22
A22 ENG−
13
TRC+ E2
R
24
A22 TRC+
20
TRC− E2
W
16
A22 TRC−
F02659
LEXUS IS200 (RM684E)
DI−255
DIAGNOSTICS
−
ABS & TRACTION CONTROL SYSTEM
INSPECTION PROCEDURE
1
Check for open and short circuit in harness and connector between terminals
ENG+, ENG−, TRC+, TRC− of ABS & TRC ECU and engine and ECT ECU
(See page IN−32).
NG
OK
Check and replace engine and ECT ECU or
ABS & TRC ECU.
LEXUS IS200 (RM684E)
Repair or replace harness or connector.