DTC B1A28: Engine control module authenticate error: Diagnosis

STEP 1. Using scan tool MB991958, diagnose the CAN bus line.
CAUTION: To prevent damage to scan tool (MB991958), always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool (MB991958).
1. Connect scan tool MB991958. Refer to DIAGNOSIS ."
2. Turn the ignition switch to the "ON" position.
3. Diagnose the CAN bus line.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the CAN bus line found to be normal?

YES : Go to Step 2.

NO : Repair the CAN bus line (Refer to DIAGNOSIS ).
STEP 2. Using scan tool MB991958, read the engine control module diagnostic trouble code.
Check again if the DTC is set in the engine control module.

Q: Is the DTC set?

YES : Troubleshoot the MFI system (Refer to DIAGNOSTIC TROUBLE CODE CHART <2.0L ENGINE> or DIAGNOSTIC TROUBLE CODE CHART <2.4L ENGINE>).

NO : Go to Step 3.
STEP 3. Using scan tool MB991958, read the diagnostic trouble code.
Check if the DTC is set in the WCM.
1. Turn the ignition switch from the "LOCK" (OFF) position to the "ON" position.
2. Check if the DTC is set.
Q: Is DTC B1761 or B2206 set other than B1A28?

YES : Perform the troubleshooting for each DTC. Refer to DTC B1761: VIN code not programmed <B1761> and DTC B2206: VIN code mismatch <B2206>.

NO : Go to Step 4.
STEP 4. Recheck for diagnostic trouble code.
Check again if the DTC is set in the WCM.
1. Turn the ignition switch from the "LOCK" (OFF) position to the "ON" position.
2. Check if the DTC is set.
Q: Is the DTC set?

YES : Replace WCM and register the ID codes (Refer to ON-VEHICLE SERVICE ). Then go to Step 5.

NO : The diagnosis is complete.
STEP 5. Recheck for diagnostic trouble code.
Check again if the DTC is set in the WCM.
1. Turn the ignition switch from the "LOCK" (OFF) position to the "ON" position.
2. Check if the DTC is set.
Q: Is the DTC set?

YES : Replace the engine control module and record VIN (Refer to HOW TO PERFORM VEHICLE IDENTIFICATION NUMBER (VIN) WRITING FOR ECM, KOS-ECU AND WCM ).

NO : The procedure is complete.