Up to 08/2009

SUSPENSION CONTROL: AIR SUSPENSION SYSTEM: C1794: Height Control OFF Switch Circuit (Test Mode DTC)
C1794 - Height Control OFF Switch Circuit (Test Mode DTC)

DESCRIPTION

If the height control OFF switch is pressed when the vehicle is stopped with the engine running or the engine switch on (IG), vehicle height control will be disabled and remain disabled even after the engine switch is turned off. In this case, "HEIGHT CONTROL OFF" will be displayed on the multi-information display in the combination meter assembly. Pressing the height control OFF switch again with the engine running or the engine switch on (IG) will resume the vehicle height control. If the vehicle speed reaches approximately 30 km/h when the vehicle height control is disabled, vehicle height control will automatically resume.





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
- Before performing troubleshooting, inspect the connectors of related circuits.
- Before replacing the suspension control ECU, perform all of the following again: 1) symptom simulation How To Proceed With Troubleshooting; 2) DTC inspection Reading and Clearing Diagnostic Trouble Codes; and 3) Techstream inspection (Data List or Active Test) Scan Tool Testing and Procedures. 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. INSPECT HEIGHT CONTROL OFF SWITCH

(a) Disconnect the height control OFF switch connector.





(b) Measure the resistance according to the values in the table below.

Standard resistance:





Text in Illustration





NG -- REPLACE HEIGHT CONTROL OFF SWITCH
OK -- Continue to next step.

2. CHECK HARNESS AND CONNECTOR (HEIGHT CONTROL OFF SWITCH - ECU AND BODY GROUND)

(a) Disconnect the A56 ECU connector.





(b) Disconnect the F18 height control OFF switch connector.

(c) Measure the resistance according to the values in the table below.

Standard resistance:





Text in Illustration





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE SUSPENSION CONTROL ECU