Check engine light is on. Is the Lexus dealer the only place that can diagnose. on 2002 Lexus RX300

The dealer wants $100 to lift the hood. What might be the total cost?

Asked by for the 2002 Lexus RX300
No any shop can pull the code, most auto parts stores such as auto zone or advance auto will pull code for free, and tell you possible poblem coul be as simple as loose gas cap