I just bought this truck last week and the guy I bought it from told me it needed an O2 sensor.I replaced this yesterday and the check engine light is still on.(The truck does run better now with the new sensor.)I read an earlier post about clearing the light on a B2600 and tried it but it didn't work.Anybody have any other ideas?Thanks

My Truck has the same problem.
Please need some help also.
Thanks.

The check engine light is intended to come on at specific mileages on the odometer, on my truck at 60,000 and 120,000 for example. When the truck is int he shop, the mechanic finds a set of three wires under the dash on the left side of the steering column, two wires on one side, one wire on the other side, two of the wires are plugged together. On the side with the two wires, disconnect the one and connect the other to make the light go out. Sorry, I don't recall the colors of the wires.

I'm so glad I've gotten rid of most of the computer crap on my truck.

Thanks to Les. I took a look today and right beside the hood release cable to the left of the steering column were 3 wires. There was a black wire with a white connector connected to a brown wire with a white stripe and a black connector.Right next to them with the same type white connector was a green wire. I disconnected the brown from the black and connected the green and black and the check engine light is out.Everything works fine.

Thanks again !

Ed