C1745

SUSPENSION CONTROL: AIR SUSPENSION SYSTEM: C1745/45: Exhaust Solenoid
C1745/45 - Exhaust Solenoid

DESCRIPTION

The suspension control ECU operates the exhaust solenoid valve (height control compressor), releases the air from the height control cylinder assembly (pneumatic cylinder) and lowers the vehicle height.

When the vehicle height is lowered, the suspension control ECU opens the height control valve and then operates the exhaust solenoid valve to release compressed air to the outside.

The exhaust solenoid valve is on the compressor unit and has only one valve.





HINT
- Once the suspension control ECU stores DTC C1745/45 in memory, vehicle height control is suspended until a normal signal is input to the suspension control ECU from the exhaust solenoid valve. However, control is resumed if the engine switch is turned off and then on (IG) again.
- Malfunction in the exhaust solenoid valve:
Height control indicator N comes on or blinks and HI and LO do not come on by operating the height control switch "up" or "down".

WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
When replacing the suspension control ECU, perform registration Programming and Relearning.

HINT
If DTC C1782/82 is output at the same time as C1745/45, perform the inspection necessary for DTC C1782/82 first C1782.

PROCEDURE

1. PERFORM ACTIVE TEST USING TECHSTREAM (EXHAUST SOLENOID)

(a) Turn the engine switch off.

(b) Connect the Techstream to the DLC3.

(c) Turn the engine switch on (IG).

(d) Turn the Techstream on.

(e) Enter the following menus: Chassis / Air suspension / Active Test.

Air Suspension





OK:

Operation of solenoid (clicking sound) can be heard.

Result





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

B -- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Air Suspension System
A -- Continue to next step.

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

(a) Disconnect the S9 exhaust solenoid valve connector.

(b) Disconnect the R22 suspension control ECU connector.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

3. INSPECT HEIGHT CONTROL COMPRESSOR (EXHAUST SOLENOID VALVE)

(a) Turn the engine switch off.

(b) Remove the height control compressor Removal.

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





Standard Resistance:





Text in Illustration





(d) Connect the positive (+) lead of the battery to terminal 2 (L) and the negative (-) lead to terminal 1 (B) of the solenoid valve connector. Then check that the valve makes an operating sound.

OK:

Operation of solenoid (clicking sound) can be heard.

NG -- REPLACE HEIGHT CONTROL COMPRESSOR ASSEMBLY Removal

OK -- REPLACE SUSPENSION CONTROL ECU Removal