Up to 08/2009

SUSPENSION CONTROL: AIR SUSPENSION SYSTEM: C1745: Exhaust Solenoid Valve Circuit Malfunction
C1745 - Exhaust Solenoid Valve Circuit Malfunction

DESCRIPTION

The exhaust valve built into the height control compressor assembly opens to discharge compressed air from the pneumatic cylinders into the atmosphere according to the signal from the suspension control ECU.





WIRING DIAGRAM





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 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 COMPRESSOR ASSEMBLY (EXHAUST VALVE)

(a) Turn the engine switch off.

(b) Disconnect the exhaust valve connector.





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

Standard resistance:





Text in Illustration





(d) Inspect if the exhaust valve is stuck:

(1) Connect a positive (+) lead from the battery to terminal 2 (B) and a negative (-) lead to terminal 1 (L).

(2) Check the operating sound of the exhaust valve.

OK:

It makes an operating sound (click).

NG -- REPLACE HEIGHT CONTROL COMPRESSOR ASSEMBLY Removal
OK -- Continue to next step.

2. CHECK HARNESS AND CONNECTOR (EXHAUST VALVE - SUSPENSION CONTROL ECU AND BODY GROUND)

(a) Turn the engine switch off.

(b) Disconnect the A54 ECU connector.

(c) Disconnect the O27 exhaust solenoid valve connector.

(d) Measure the resistance according to the value(s) in the table below.





Standard resistance:





Text in Illustration





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE SUSPENSION CONTROL ECU