P0037, p0031, p0032,p0131,p0134

I would be checking for voltage on the heater pins at the O2 sensor connectors. Both sensors share the same power supply for heater circuit, it's a 10A fuse labeled "ENG BAR 3" in the underhood fuse box by the battery so if that fuse goes out then you will end up with a code for both sensors. I would be very suspicious on that spliced on connector, a car with federal emissions DOES only have two sensors and upstream sensor should have 5 pins, not 4. Pull the tape off and see what it looks like. For whatever reason, Mazda stupidly made two of the wires the same color so I'm willing to bet that whoever spliced the connector on connected those wires together, which probably blew the fuse. Get the correct upstream connector, wire it all in, and install the correct sensor. You may have to go to the dealer or junkyard for the connector as I couldn't find a listing for it aftermarket. The rear sensor is also listed as being a different part between federal and CA emission so I would make sure that one is correct as well.

Grendel65 said:

Couple of things to add. If you are looking for a good diagnostic technician, find a shop that uses ASE Certified Technician and that at least one is currently certified. You will know these shops because it will have the ASE blue sign somewhere it can be seen. These individuals that are current in the last 10-15 years test to get re-certified or certified/ The testing on the diagnostic side of the testing is extensive.
The suggestion would be better to take you Mazda to a Auto Electric service shop because of those pictures of the wiring posted . I say this because a higher majority of service shop won't touch your car because of the wiring changes you or the previous owner did.
I am sure madmatt2024 will concur.... we like his shop turn down many interesting electrical jobs like these done by good intended DIYs.

Click to expand...

Actually, my opinion is pretty much the opposite. We don't typically turn down jobs, let alone one like OP's. If a shop doesn't want to touch a vehicle simply based on OP's wiring pictures, then I wouldn't think very much of that place. Easy money like brakes and oil changes are all they are after. ASE certification also doesn't mean much to me, when you actually take a step back it really looks like a money making scheme. Not to mention, ANYBODY with an ASE cert can call themselves "ASE certified" but that doesn't mean that they are master techs or even have a cert in the area required for the work that needs to be done on your vehicle. Nobody in my shop has current ASE certification, yet we are usually the place that people get sent for diagnostic work when several other shops can't fix the issue. We've even had to clean up after "ASE Certified" techs that did sloppy or incorrect work.

Grendel65 said:

Ok well your going to be one of those that thinks they know because they do and not trained.... LOL
often on forums those that don't have certification post like yours . LOL!
BTW anyone that has an ASE certification generally keeps them hung in plain view for customers to see.

As for your shop taking on a wiring mess like the one pictured in this thread, you would be a rare one and I can see your shop charging a butt load to correct it. That is also why we turn those away the customer may get the issue resolved but always feel like the cost was unfair.

In the end your shop I would say is one that people should be weary of using and who they have working on their vehicles.

Education and training are always better then practicing and learning at the expense of the customer.

Click to expand...

First off, I have to apologize to Rockjr91 for going off topic on this.

I admit, I can be a bit argumentative at night and I'm sorry because I can see now that I really came off that way. But, how can you just laugh and turn you nose up at someone over a piece of paper? That's just sad.

I have to ask: Why would you, a CorkSport employee that (from what I can gather) does ECU tuning , be doing general repair work at CorkSport?
On top of that, this isn't even that big of a "wiring mess". I would rather diag. and fix this than fix CAN bus issues on most cars. If you wouldn't work on it because "the cost was unfair" then do you basically tell the customer to junk the car? It's still probably going to be cheaper to fix this issue than to replace the vehicle. If you're an ASE "master tech" then you should be able to easily figure this out in the standard 1hr diag. time and spend another hour or two to rewire the sensors or source and and replace the harness. You do specialize in Mazdas after all.

I've apprenticed for years to get where I am now, I'm not untrained. Never once did I "learn at the expense of the customer", I learned at the expense of the shop, they openly acknowledged it when they first hired me. This shop pays hourly so at no point are techs under the gun to pump out work for book time or trying to cram 10hr of work into an 8hr shift. If we go overtime due to a tech screwup, we charge book time. Generally, if we go over due to the vehicle condition, we bill extra but If we come in under time, we charge less than book. The shop also supplies all of our tools and boxes. This shop has been in the same family since 1945 and this is just the way they have always done things. I admit, the place I work isn't perfect and neither am I, but to call us a place to be "weary of" without ever meeting us or seeing our workmanship is just plain arrogant.