C1789 Code: Meaning, Causes, and Symptoms | OBD2 Codes
C1789 – L4 Switch Circuit Malfunction
C1789 Possible Symptoms
Anti-Lock Brake System (ABS) Warning Light ON,Engine Light ON (or Service Engine Soon Warning Light)
C1789 Possible Causes
Faulty L4 Switch Circuit,L4 Switch Circuit harness is open or shorted,L4 Switch Circuit circuit poor electrical connection,Faulty Suspension Control ECU
This circuit is sending the signal to the Suspension Control ECU by detecting that the transfer shift lever is in L4 position.