Inspection Procedure

WARNING: This page is about a different car, the 2008 Lexus LS 600hL. However, it is still accessible from the selected car via links, so may be relevant.

RESET MAYDAY ECU

Exit diagnosis mode and wait for 10 seconds.
Disconnect the cable from the negative (-) battery terminal.
NOTE:
- After the power switch is turned OFF, the HDD navigation system requires approximately 6 minutes to record various types of memory and settings. As a result, after turning the power switch OFF, wait 6 minutes or more before disconnecting the cable from the negative (-) battery terminal.
- When disconnecting the cable, some systems need to be initialized after the cable is reconnected (see INITIALIZATION ).
Reconnect the cable to the negative (-) battery terminal, and wait for 10 seconds.
NOTE: When disconnecting the cable, some systems need to be initialized after the cable is reconnected (see INITIALIZATION ).
Turn the power switch ON (IG), and then check for the current DTC and historic DTC again (see DTC CHECK / CLEAR ).

Result

RESULT CHART

Result	Proceed to
Current DTC 2-1 or 2-2 exists	A
Historic DTC 2-1 or 2-2 exists	B

B: CLEAR HISTORIC DTC (See DTC CHECK / CLEAR )

A: Go to next step

CHECK MAYDAY ECU
1. Press the SERVICES button and check the LEXUS Link condition with the LEXUS Link call center
  OK: System operates normally.
  
  NG:
  
  System does not connect to LEXUS Link call center. (Current DTC 2-1 or 2-2 exists.)
  
  NG: REPLACE MAYDAY ECU TOGETHER WITH MAYDAY BATTERY AND THEN PERFORM REGISTRATION
  
  OK: END