C1752

SUSPENSION CONTROL: AIR SUSPENSION SYSTEM: C1752: Height Control Compressor Motor Circuit Malfunction
C1752 - Height Control Compressor Motor Circuit Malfunction

DESCRIPTION

The signal from the suspension control ECU turns on the suspension control relay. At that time, auxiliary battery voltage is input to the height control compressor motor through the suspension control relay. The height control compressor motor starts.





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 Electronic Circuit Inspection Procedure; 2) DTC inspection; and 3) the 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.

PROCEDURE

1. INSPECT SUSPENSION CONTROL RELAY (AIR SUS)

(a) Turn the power switch OFF.

(b) Remove the suspension control relay from the engine room No. 5 relay block.





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

Standard resistance:





NG -- REPLACE SUSPENSION CONTROL RELAY
OK -- Continue to next step.

2. CHECK HARNESS AND CONNECTOR (COMPRESSOR - ECU, AUXILIARY BATTERY AND BODY GROUND)

(a) Remove the suspension control relay from the engine room No. 5 relay block.





(b) Measure the voltage according to the value(s) in the table below.

Standard voltage:





(c) Disconnect the A57 compressor connector.





(d) Disconnect the A39 ECU connector.

(e) 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 (COMPRESSOR MOTOR)

(a) Remove the height control compressor Removal.





(b) Apply 12 V battery voltage to the compressor motor and check the operation of the motor.

OK:





NOTICE:
- Do not allow the motor to operate for approximately 60 seconds or more.
- If the compressor is shorted, locked, or has a similar type of malfunction, a large amount of current will be flowing. Therefore, if the motor does not operate, immediately stop this inspection.

NG -- REPLACE HEIGHT CONTROL COMPRESSOR Removal

OK -- REPLACE SUSPENSION CONTROL ECU Removal