The voltage after the A/C relay is used to supply power to the A/C compressor magnetic clutch. When the A/C switch is turned on, applies the battery voltage to the ECM. When A/C ON signal is input, A/C power relay coil is energized to turn on the relay switch, which activates the A/C compressor magnetic clutch by the ECM. In case of the A/C relay failure, the engine symptoms will be deactivated A/C compressor magnetic clutch.
If the A/C relay circuit is short to battery line or open during two driving cycles, this code will be set.
DTC NO. | Detecting Condition | Possible Cause |
C 018 C 019 | ● C 018 Short circuit to battery line ● C 019 Open circuit : ① Short circuit to ground ② Wire broken ③ Too high temperature in power stage ● Engine Condition : IG ON ● Fuel Limit : NO ● Fuel Cut : NO ● EGR OFF : NO ● MIL : NO | ● Open or short in circuit ● Relay ● ECM |
