Slip Indicator Light Does Not Come ON: Description
WARNING: This page is about a different car, the 2007 Lexus RX 350. However, it is still accessible from the selected car via links, so may be relevant.
The skid control ECU is connected to the combination meter via CAN and multiplex communications. The SLIP indicator will come on in these cases (See TERMINALS OF ECU ) (refer to "DESCRIPTION").