Last Modified: 4-30-2014 6.6 C Doc ID: RM0000018HR000X
Model Year: 2006 Model: LX470 Prod Date Range: [05/2005 -           ]
Title: MULTIPLEX COMMUNICATION: MULTIPLEX COMMUNICATION SYSTEM: B1201; Mayday ECU Communication Stop; 2006 MY LX470 [05/2005 -        ]

DTC

B1201

Mayday ECU Communication Stop

DESCRIPTION

  • This DTC is output when communication stops between the telephone ECU (mayday ECU) and multiplex network body ECU (main).

    DTC No.

    DTC Detection Condition

    Trouble Area

    B1201

    No signal from Telephone ECU assembly (Mayday ECU) for more than 10 seconds.
    • Telephone ECU assembly (Mayday ECU)
    • Wire harness

WIRING DIAGRAM

Refer to DTC B1214 and 1215 2006 MY LX470 [05/2005 -        ]; MULTIPLEX COMMUNICATION: MULTIPLEX COMMUNICATION SYSTEM: B1214,B1215; Short to B+ in Door System Communication Bus Malfunction+ .

INSPECTION PROCEDURE

PROCEDURE

1.

CHECK TELEPHONE ECU ASSEMBLY (MAYDAY ECU)

(a) Check that the telephone can make a call.

HINT:

In this inspection, whether or not the telephone ECU (mayday ECU) functions normally can be diagnosed.

NG

REPLACE TELEPHONE ECU ASSEMBLY (MAYDAY ECU)

OK

2.

CHECK WIRE HARNESS (TELEPHONE ECU ASSEMBLY (MAYDAY ECU) - SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY (SLIDING ROOF ECU))

(a) Disconnect the ECU connectors mentioned in the table below.

(b) Check the continuity of the wire harness between the connectors.

Wire harness side connector of ECU

Terminal

Telephone ECU assembly (Mayday ECU) - Sliding roof drive sub-assembly (Sliding roof ECU)

M14-23 (MPX1) - M2-1 (MPX1)

OK:

There is continuity between the connectors.

HINT:

If there is an open in any wire harness, repair it.

NG

REPAIR OR REPLACE HARNESS AND CONNECTOR

OK

REPLACE SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY (SLIDING ROOF ECU)