DTC 4-1

CELLULAR COMMUNICATION: LEXUS LINK SYSTEM: 4-1: Red LED Error

DTC 4-1 - Red LED Error

DESCRIPTION

This DTC is stored when one of the following occurs: 1) the telephone ECU assembly is malfunctioning; 2) the red LED is malfunctioning; or 3) the wire harness between the telephone ECU assembly and map light (mayday switch) is open or shorted.






WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK HARNESS AND CONNECTOR (TELEPHONE ECU ASSEMBLY - MAP LIGHT ASSEMBLY)





(a) Disconnect the P3 ECU connector.
(b) Disconnect the R12 map light connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR THEN CLEAR HISTORIC DTC
OK -- Continue to next step.
2. CHECK MAP LIGHT ASSEMBLY (RED LED OPERATION)
(a) Temporarily replace the map light with a new or normally functioning one Removal.
(b) Check that the system operates normally.
OK:
Red LED operates normally.
NG -- REPLACE TELEPHONE ECU ASSEMBLY TOGETHER WITH MAYDAY BATTERY
OK -- END (MAP LIGHT (RED LED) IS FAULTY; CLEAR HISTORIC DTC)
3. REPLACE TELEPHONE ECU ASSEMBLY TOGETHER WITH MAYDAY BATTERY
NEXT -- PERFORM REGISTRATION