Inspection Procedure

WARNING: This page is about a different car, the 2003 Lexus LS 430. However, it is still accessible from the selected car via links, so may be relevant.

Check telephone ECU (Mayday ECU).
CHECK:

Check that the malfunction disappears when a good telephone ECU (Mayday ECU) is installed.

RESULT:

A: Malfunction does not disappear.

B: Malfunction disappears.
1. A: Replace telephone ECU (Mayday ECU) (See HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE ).
2. B: Check and replace back-up battery (portablephone-L battery) (See HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE ).