C1840 Code: Meaning, Causes, and Symptoms | OBD2 Codes

C1840 – Air Suspension Disable Switch Circuit Failure

 

C1840 Possible Symptoms

 

Anti-Lock Brake System (ABS) Warning Light ON,Engine Light ON (or Service Engine Soon Warning Light)

 

C1840 Possible Causes

 

Faulty Air Suspension Disable Switch,Air Suspension Disable Switch harness is open or shorted,Air Suspension Disable Switch circuit poor electrical connection,Faulty Air Suspension Control Module

 

C1840 Description

 

The Air Suspension Control Module monitors the Air Suspension Disable Switch. The Air Suspension Disable Switch sets the OBDII code when the Air Suspension Compressor Relay is not to factory specifications.