2007 Chevrolet Malibu P0036, P0141, P0054

He said he checked all the fuses and they're fine. He said there's no battery voltage in the circuit for the O2 sensors in the fuse block.

If there's no battery voltage to the O2 sensor fuses in the fuse block does that mean I need to replace the fuse block? Or does that just mean there's a shorted wire somewhere? Could the shorted wire be inside the fuse block?

Thank you! I had another issue with the wire from the TCM to the fuse box and they replaced that (which fixed the majority of my issues). I'm thinking that wire might have shorted something in the fuse box (maybe the O2 circuit) and I'm hoping that replacing the fuse box will fix it. The mechanic said he's 100% sure there's a problem with the fuse box itself - either from corrosion, water or an open circuit.

Do you think I should take it back to the mechanic and have them test the wires to my O2 sensor? The only thing he said was that there's no battery voltage at the O2 sensor fuses in the fuse block and that the wires "visually" looked fine. If I had an open circuit before the fuse block would the wires still look fine? I just don't want to pay $300 for the fuse block then find out it was just a wire before it that needed to be replaced. I also don't really want to pay them $100 just to look at it all over again but if I have to, I will.

Thank you! I asked the mechanic if he could test the wires but he said they wouldn't have any charge since there's no voltage at the fuse box. He said when he replaces the fuse box he'll hook it up to their diagnostic tool to make sure the circuit is working properly.

He said he's 99% sure there's no issue with the wires and 100% sure I need a new fuse box. I'm going to have him put in the fuse box (whenever it gets here - no one has it since it's on back order with GM) and see if that works. If it doesn't, they'll likely help me out with it since he told me and the manager there that he's 100% sure about it. When he showed me what was wrong, he said the circuit inside the fuse box provides power to the wires to the O2 sensors and that the circuit had no battery voltage reading. Basically, it looked like the wires were dead since they weren't getting any power from the fuse box. I've ordered the fuse box, so I guess I'll see if it works or not! Thanks for your help!