DESCRIPTION
The circuit is used to send TRAC and VSC control information from the skid control ECU (brake actuator assembly) to the ECM, and engine control information from the ECM to the skid control ECU (brake actuator assembly) through the CAN communication system.
for 4WD or w/ Rear Differential Lock:
The rear differential lock identification signal is sent from the 4 wheel drive control ECU to the skid control ECU (brake actuator assembly) via the CAN communication system.
DTC No. |
Detection Item |
DTC Detection Condition |
Trouble Area |
---|---|---|---|
C1203 |
ECM Communication Circuit Malfunction |
Any of the following is detected:
|
|
HINT:
DTC will be output when conditions for any of the patterns in the table above are met.
CAUTION / NOTICE / HINT
NOTICE:
When replacing the skid control ECU (brake actuator assembly), perform zero point
calibration and store system information (See page
).
HINT:
When DTC C1203, inspect and repair the trouble areas indicated.
PROCEDURE
1. |
CHECK PART NUMBER (ECM) |
(a) Check that the proper ECM is installed.
Result
Result |
Proceed to |
---|---|
Proper ECM is installed (for 4WD or w/ Rear Differential Lock) |
A |
Proper ECM is installed (except 4WD or w/o Rear Differential Lock) |
B |
Proper ECM are not installed |
C |
B | ![]() |
GO TO STEP 3 |
C | ![]() |
CHECK OR REPLACE CHARGING SYSTEM OR BATTERY |
|
2. |
CHECK PART NUMBER (4 WHEEL DRIVE CONTROL ECU) |
(a) Check that a proper 4 wheel drive control ECU is installed.
Result
Result |
Proceed to |
---|---|
Proper 4 wheel drive control ECU is installed |
A |
Proper 4 wheel drive control ECU are not installed |
B |
B | ![]() |
REPLACE 4 WHEEL DRIVE CONTROL ECU |
|
3. |
CHECK BRAKE ACTUATOR ASSEMBLY |
(a) Check if the brake actuator assembly had been replaced before the DTC was recorded.
Result
Result |
Proceed to |
---|---|
The brake actuator assembly is not replaced |
A |
The brake actuator assembly is replaced |
B |
B | ![]() |
GO TO STEP 5 |
|
4. |
RECONFIRM DTC |
(a) Clear the DTC (See page
).
(b) Turn the ignition switch off.
(c) Check if the same DTC is recorded (See page
).
Result |
Proceed to |
---|---|
DTC C1203 is not output |
A |
DTC C1203 is output |
B |
A | ![]() |
USE SIMULATION METHOD TO CHECK |
B | ![]() |
REPLACE BRAKE ACTUATOR ASSEMBLY |
5. |
PERFORM INITIALIZATION AND CALIBRATION |
(a) Perform initialization and calibration (See page
).
|
6. |
RECONFIRM DTC |
(a) Clear the DTC (See page
).
(b) Turn the ignition switch off.
(c) Check if the same DTC is recorded (See page
).
Result |
Proceed to |
---|---|
DTC C1203 is not output |
A |
DTC C1203 is output |
B |
A | ![]() |
END |
B | ![]() |
REPLACE BRAKE ACTUATOR ASSEMBLY |
Terminals Of Ecu
TERMINALS OF ECU
1. AIRBAG SENSOR ASSEMBLY
Terminal No.
Terminal Symbol
Destination
A21-1
P2+
Instrument panel passenger without door airbag assembly (Front passenger
side squib 2nd step)
A21-2
...
On-vehicle Inspection
ON-VEHICLE INSPECTION
PROCEDURE
1. INSPECT SIDE AIRBAG SENSOR ASSEMBLY (for Vehicle not Involved in Collision)
(a) Perform a diagnostic system check (See page
).
2. INSPECT SIDE AIRBAG SENSOR ASSEMBLY (for Vehicle Involved in Collision and
Airbag has not Deployed)
(a) Perform a diagnostic s ...
On-vehicle Inspection
ON-VEHICLE INSPECTION
PROCEDURE
1. INSPECT CURTAIN SHIELD AIRBAG ASSEMBLY (for Vehicle not Involved in Collision)
(a) Perform a Diagnostic System Check (See page
).
(b) With the curtain shield airbag installed on the vehicle, perform
a visual check. If any of the defects mention ...