1. AFLS ECU
2. Swivel Actuator
LIN (Local Interconnect Network) is direct communication system to low-cost for electric system of vehicle. AFLS ECU controls the position of headlamp by using LIN which calculates input signals of height sensor, vehicle speed and steering wheel position.Swivel Actuator controls left / right position of Headlamp, ISM(Intelligent Stepper Motor) controls up/down position of headlamp.
If this LIN communication error of left Swivel Actuator occurs, this B1639 code is set. And that AFLS warning lamp is turned on in the cluster.
Item
Detecting Condition
Possible Cause
DTC Strategy
Signal monitoring
LIN Communication circuit is opened/shorted
Left Swivel Motor connection is opened
Faulty ISM of left side headlamp
Enable Conditions
IG ON
Threshold Value
Left Swivel Actuator LIN communication error
Detecting time
1 sec.
Fail Safe
Swivelling : stop at present status.
Levelling : stop at present status.
Check Lamp
AFLS warning lamp on
Fig.1) LIN communication Signal Waveform