The Check Engine Light may illuminate due to an O2 sensor heater fault. Most commonly the affected O2 sensor will need to be replaced to correct this concern.
Car Problem Reports
Lexus LS430 Check Engine LIght With Code P0135, P0141, P0155, or P0161
Lexus LS430 Problem
Average Mileage: 106,357 mi (68,000 mi - 134,500 mi)
Visitor, 2002 Lexus LS430, 68,000 mi
Visitor, 2001 Lexus LS430, 134,500 mi
my check engine light came on-care is running fine, it seems..what could this be?
check engine light on code po155 replaced by lexus at £179
Visitor, 2002 Lexus LS430, 91,000 mi
The o2 sensor light kept coming on and it had to be replaced.