Lexus ES: ECM Communication (C124A00)
DESCRIPTION
If the vehicle information stored by the skid control ECU (brake actuator assembly) does not match that sent from the ECM or a new skid control ECU (brake actuator assembly) is installed and the vehicle information has not been stored, this DTC is stored.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area |
|---|---|---|---|
| C124A00 | ECM Communication | Engine, drive source and destination information sent from the ECM does not match the information of the skid control ECU or there is no information in memory. |
|
CAUTION / NOTICE / HINT
NOTICE:
After replacing the skid control ECU (brake actuator assembly), perform acceleration sensor zero point calibration and store system information memorization.
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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 | .gif) | REPLACE ECM |
|
| 2. | CHECK PART NUMBER (BRAKE ACTUATOR ASSEMBLY) |
(a) Check that a proper skid control ECU (brake actuator assembly) is installed.
OK:
Proper skid control ECU (brake actuator assembly) is installed.
(b) Check if the skid control ECU (brake actuator assembly) had been replaced before the DTC was stored.
OK:
Skid control ECU (brake actuator assembly) had not been replaced.
| Result | Proceed to |
|---|---|
| OK | A |
| NG (The skid control ECU (brake actuator assembly) had been replaced.) | B |
| NG (A proper skid control ECU (brake actuator assembly) is not installed.) | C |
| A | | REPLACE BRAKE ACTUATOR ASSEMBLY |
| C | | REPLACE BRAKE ACTUATOR ASSEMBLY |
|
| 3. | CONFIRM SYSTEM INFORMATION STORAGE |
(a) Check that Store System Information (acceleration sensor zero point calibration and store system information memorization) has been performed.
OK:
Store System Information has been performed.
HINT:
After installing a new skid control ECU (brake actuator assembly), DTCs C051D54 and C124A00 will be stored until system variant learning (acceleration sensor zero point calibration and store system information memorization) is performed.
| OK | | REPLACE BRAKE ACTUATOR ASSEMBLY |
| NG | | PERFORM ACCELERATION SENSOR ZERO POINT CALIBRATION AND STORE SYSTEM INFORMATION MEMORIZATION |
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