Last Modified: 4-30-2014 6.6 C Doc ID: RM000001EGB000X
Model Year: 2006 Model: LX470 Prod Date Range: [05/2005 -           ]
Title: CELLULAR COMMUNICATION: LEXUS LINK SYSTEM: 6-4; Backup Battery Connection Error; 2006 MY LX470 [05/2005 -        ]

DTC

6-4

Backup Battery Connection Error

DESCRIPTION

After the ignition switch is turned ON and 10 seconds or more have passed, if the mayday ECU assembly does not recognize the mayday battery (backup battery), this DTC is output.

HINT:

This DTC is only a historic DTC.

DTC No.

DTC Detection Condition

Trouble Area

6 - 4

Communication or communication line is abnormal between mayday ECU and mayday battery
  • Mayday ECU assembly
  • Mayday battery (Backup battery)
  • Wire harness

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1.

CHECK WIRE HARNESS (MAYDAY ECU ASSEMBLY - MAYDAY BATTERY)

(a) Disconnect the M15 ECU connector.

(b) Disconnect the M13 battery connector.

(c) Measure the resistance of the wire harness side connectors.

Standard resistance:

Tester Connection

Specified Condition

M15-2 (BBI+) - M13-1 (BBO+)

Below 1 Ω

M15-9 (BBI-) - M13-2 (BBO-)

Below 1 Ω

M15-2 (BBI+) or M13-1 (BBO+) - Body ground

10 kΩ or higher

M15-9 (BBI-) or M13-2 (BBO-) - Body ground

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS AND CONNECTOR THEN CLEAR HISTORIC DTC

OK

2.

REPLACE MAYDAY BATTERY (BACKUP BATTERY)

(a) Perform registration 2006 MY LX470 [05/2005 -        ]; CELLULAR COMMUNICATION: LEXUS LINK SYSTEM: REGISTRATION+ .

(b) Check for DTC again.

OK:

No DTCs output.

NG

REPLACE MAYDAY ECU ASSEMBLY THEN PERFORM REGISTRATION

OK

END (MAYDAY BATTERY IS FAULTY; CLEAR HISTORIC DTC)