DESCRIPTION
DTC No. | Detection Item | DTC Detection Condition | Trouble Area |
---|---|---|---|
C124A00 | ECM Communication | Any of the following is detected:
|
|
Vehicle Condition | ||||
---|---|---|---|---|
Pattern 1 | Pattern 2 | Pattern 3 | ||
Diagnosis Condition | - | - | - | - |
Malfunction Status | The engine type, powertrain variation, engine stop and start ECU availability and destination information sent from the ECM do not match the information stored in the skid control ECU (brake actuator assembly) | ○ | - | - |
No system information stored in the skid control ECU (brake actuator assembly) | - | ○ | - | |
When the skid control ECU (brake actuator assembly) is malfunctioning | - | - | ○ | |
Detection Time | - | - | - | |
Number of Trips | 1 trip | 1 trip | 1 trip |
HINT:
DTC will be output when conditions for any of the patterns in the table above are met.
CAUTION / NOTICE / HINT
NOTICE:
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PROCEDURE
1. | CHECK PART NUMBER (ECM) |
(a) Check that the proper ECM is installed.
OK:
Proper ECM is installed.
(b) Check if the ECM was replaced before the DTC was stored.
OK:
ECM was not replaced
Result | Proceed to |
---|---|
OK | A |
NG (A proper ECM is not installed and/or the ECM was replaced.) | B |
B | ![]() | REPLACE ECM |
|
2. | CHECK PART NUMBER (BRAKE ACTUATOR ASSEMBLY) |
(a) Check that the proper brake actuator assembly is installed.
OK:
Proper brake actuator assembly is installed.
(b) Check if the brake actuator assembly was replaced before the DTC was recorded.
OK:
The brake actuator assembly was not replaced.
Result | Proceed to |
---|---|
OK | A |
NG (The brake actuator assembly was replaced.) | B |
NG (A proper brake actuator assembly is not installed.) | C |
C | ![]() | GO TO STEP 5 |
B | ![]() | REPLACE BRAKE ACTUATOR ASSEMBLY |
|
3. | CLEAR DTC |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Operate the Techstream to clear the codes. Enter the following menus: Chassis / Brake/EPB / Trouble Codes.
Chassis > Brake/EPB > Clear DTCs(d) Press the DTC clear button.
(e) Turn the engine switch off.
|
4. | RECONFIRM DTC |
(a) Turn the engine switch on (IG).
(b) Read the DTCs following the prompts on the Techstream. Enter the following menus: Chassis / Brake/EPB / Trouble Codes.
Chassis > Brake/EPB > Trouble Codes(c) Check if the same DTC is output.
Result | Proceed to |
---|---|
DTC C124A00 is not output. | A |
DTC C124A00 is output. | B |
A | ![]() | USE SIMULATION METHOD TO CHECK |
B | ![]() | REPLACE BRAKE ACTUATOR ASSEMBLY |
5. | CHECK CALIBRATION |
(a) After replacing the skid control ECU (brake actuator assembly), check that "Calibration" is performed.
HINT:
If a new skid control ECU (brake actuator assembly) was installed, C121054 and C051D54 are output before "Calibration" is performed.
Result | Proceed to |
---|---|
Calibration performed | A |
Calibration not performed | B |
A | ![]() | REPLACE BRAKE ACTUATOR ASSEMBLY |
B | ![]() | PERFORM CALIBRATION |
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