From 08/2009

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 power management control ECU is installed.





INSPECTION PROCEDURE

NOTICE:
- Before performing troubleshooting, inspect the connectors of related circuits.
- If DTC C1782 (Power Source Voltage Malfunction) is output at the same time, perform troubleshooting for C1782 first C1782.
- Before replacing the suspension control ECU, perform all of the following again: 1) symptom simulation How To Proceed With Troubleshooting; 2) DTC inspection Air Suspension System; and 3) Techstream inspection (Data List or Active Test) Air Suspension System. If no malfunctions are found in other areas, replace the suspension control ECU.
- If the suspension control ECU is replaced, the vehicle height offset calibration and registration of vehicle identification information must be performed Calibration and Registration)
PROCEDURE

1. CHECK DTC (C1781)

(a) Check for DTC C1781 Air Suspension System

Result:





B -- REPLACE SUSPENSION CONTROL ECU
A -- Continue to next step.

2. REGISTRATION OF VEHICLE IDENTIFICATION INFORMATION

(a) Perform registration of vehicle identification information Registration

NEXT -- Continue to next step.

3. CHECK DTC (C1789)

(a) Check for DTC C1789 Air Suspension System

Result:





B -- CHECK CAN COMMUNICATION SYSTEM

A -- END

1. CHECK CAN COMMUNICATION SYSTEM

(a) Check the CAN communication system for any malfunctions Diagnosis System.

Result:





B -- GO TO CAN COMMUNICATION SYSTEM How to Proceed With Troubleshooting
A -- Continue to next step.

2. CHECK POWER MANAGEMENT CONTROL ECU

(a) Check if the part number of the installed power management control ECU is correct.

OK:

A power management control ECU with the correct part number is installed.

NG -- REPLACE POWER MANAGEMENT CONTROL ECU Removal

OK -- REPLACE SUSPENSION CONTROL ECU