C1789

SUSPENSION CONTROL: AIR SUSPENSION SYSTEM: C1789: Vehicle Identification Malfunction
C1789 - Vehicle Identification Malfunction

DESCRIPTION

- This DTC is stored when the suspension control ECU is initialized, and is cleared when the vehicle identification information received through CAN communication is correctly stored in the EEPROM.

- DTC C1789 is stored as the vehicle specification and data do not match when an incorrect hybrid vehicle control ECU or AFS ECU is installed.





INSPECTION PROCEDURE

NOTICE:
- Before performing troubleshooting, inspect the connectors of related circuits.
- If DTC C1782 is output at the same time, perform troubleshooting for DTC C1782 first C1782.
- If the suspension control ECU is replaced with a new one, enter test mode and perform registration of vehicle identification information Programming and Relearning.
- Do not exchange the suspension control ECU with a normally functioning one from another vehicle to perform troubleshooting.

PROCEDURE

1. CHECK VEHICLE IDENTIFICATION INFORMATION STATUS

(a) Check that vehicle identification information has been stored Programming and Relearning.

Result





B -- PERFORM VEHICLE IDENTIFICATION INFORMATION REGISTRATION Programming and Relearning
A -- Continue to next step.

2. CHECK PART NUMBER

(a) Check that the part numbers of the installed hybrid vehicle control ECU and AFS ECU are correct.

NOTICE:
When removing the hybrid vehicle control ECU and/or AFS ECU to check the part number, or when replacing the hybrid vehicle control ECU and/or AFS ECU, be sure to follow the appropriate procedures and precautions.

HINT
- Refer to the hybrid vehicle control ECU installation procedure Removal.
- Refer to the AFS ECU installation procedure Removal.

OK:

Hybrid vehicle control ECU and AFS ECU with correct part numbers are installed.

NG -- REPLACE CORRESPONDING ECU
OK -- Continue to next step.

3. CLEAR DTC

(a) Clear the DTCs Air Suspension System.

NEXT -- Continue to next step.

4. CHECK FOR DTC

(a) Check if DTC C1789 is output Air Suspension System.

OK:

DTC C1789 is not output.

HINT
If no parts are replaced and DTC C1789 is output, there may be an internal malfunction in the suspension control ECU. In this case, replace the suspension control ECU.

NG -- REPLACE SUSPENSION CONTROL ECU Removal

OK -- USE SIMULATION METHOD TO CHECK How To Proceed With Troubleshooting