I have a 2003 Duramax diesel, and I need to work on the block heater, does anyone know the location, which side of the motor it is on. Make my job go a lot faster!:)

Pass side right below the front of the exaust manifold. Takes a allen or flat tip screw driver to remove.

Thanks a lot very much appreciated!!! :):):):):)

Located in front of passenger side motor mount. Access much easier with pass. front wheel and wheelwell liner removed.

Why you working on it?
If it isn't working, make sure you don't have a defective cord.