2004 Tundra check engine light

A scan tool can read and clear the code that turn on the check engine lite.

Hi Vic,
I have a 2002 tundra and also had the check engine light come on. After using a scan tool it was determined that the #1 o2 senor in bank # 2(passenage side before the cat) was defective. I replaced the senor and cleared the code and everything is fine now. However I later found out ( after buying and replacing the senor) that there was a recall on the o2 senor. I don't know if the '04s were also included in the recall but maybe it's worth contacting the dealer.