C1761

SUSPENSION CONTROL: AIR SUSPENSION SYSTEM: C1761: Continuous Electric Current to Height Control Compressor Motor
C1761 - Continuous Electric Current to Height Control Compressor Motor

DESCRIPTION

The signal from the suspension control ECU operates the suspension control relay and the height control compressor motor starts. The height control compressor motor operates until the targeted vehicle height is reached. Then the height control sensor sends the signal to the suspension control ECU, and stops the height control compressor motor.

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 Electronic Circuit Inspection Procedure; 2) DTC inspection; and 3) Techstream inspection (Data List or Active Test). If no malfunctions are found in other areas, replace the suspension control ECU.
- If the suspension control ECU or height control sensor is replaced, the vehicle height offset calibration must be performed Programming and Relearning.
- The system may output DTC C1761 even when the system is normal if one of the following occurs: 1) the vehicle is full of passengers and the luggage compartment is full; 2) the vehicle is being driven or is stopped on an irregular surface; or 3) the air ducts are frozen.

PROCEDURE

1. CLEAR DTC

(a) Clear the DTC Reading and Clearing Diagnostic Trouble Codes.

NEXT -- Continue to next step.

2. CHECK AIR LEAKAGE

(a) Check for air leakage Operation Check.

OK:

No leaks.

NG -- REPAIR OR REPLACE AIR TUBE
OK -- Continue to next step.

3. INSPECT IF FRONT HEIGHT CONTROL VALVE IS STUCK

(a) Remove the front height control valve Removal.

(b) Check the front height control valve RH valve.

(1) Connect terminal 1 (RH+) to the battery positive (+) terminal, and terminal 2 (E) to the battery negative (-) terminal.

(2) Check the operating sound of the height control valve.

OK:

It makes an operating sound (click).

(c) Check the front height control valve LH valve.

(1) Connect terminal 3 (LH+) to the battery positive (+) terminal, and terminal 2 (E) to the battery negative (-) terminal.

(2) Check the operating sound of the height control valve.

OK:

It makes an operating sound (click).

NG -- REPLACE FRONT HEIGHT CONTROL VALVE Removal
OK -- Continue to next step.

4. INSPECT IF REAR HEIGHT CONTROL VALVE IS STUCK

(a) Remove the rear height control valve Removal.

(b) Check the rear height control valve RH valve.

(1) Connect terminal 1 (+RH) to the battery positive (+) terminal, and terminal 2 (E) to the battery negative (-) terminal.

(2) Check the operating sound of the height control valve.

OK:

It makes an operating sound (click).

(c) Check the rear height control valve LH valve.

(1) Connect terminal 3 (+LH) to the battery positive (+) terminal, and terminal 2 (E) to the battery negative (-) terminal.

(2) Check the operating sound of the height control valve.

OK:

It makes an operating sound (click).

NG -- REPLACE REAR HEIGHT CONTROL VALVE Removal
OK -- Continue to next step.

5. INSPECT IF HEIGHT CONTROL COMPRESSOR IS STUCK

(a) Remove the height control compressor Removal.

(b) Inspect if exhaust valve is stuck:

(1) Connect terminal 1 to the battery positive (+) terminal, and terminal 2 to the battery negative (-) terminal.

(2) Check the operating sound of the height control valve.

OK:

It makes an operating sound (click).

(c) Inspect if compressor is stuck:

(1) Connect terminal 1 (B) to the battery positive (+) terminal, and terminal 2 (E) to the battery negative (-) terminal.

(2) Check that the motor rotates.

CAUTION:
If the compressor is shorted, locked, or has a similar type of malfunction, a large amount of voltage will be flowing. Therefore, if the motor does not operate, immediately stop this inspection.

NOTICE:
Do not allow the motor to operate for approximately 60 seconds or more.

OK:

Motor operates

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

6. INSPECT SUSPENSION CONTROL RELAY (AIR SUS)

(a) Turn the engine switch off.

(b) Remove the suspension control relay from the engine room No. 1 relay block.

NG -- REPLACE SUSPENSION CONTROL RELAY

OK -- REPLACE SUSPENSION CONTROL ECU Removal