Help 02 sensor

V
Mazda P5
Ok I had to get a new O2 sensor but it was the dyi one. I just need to know what color is what for the connections on the secondary O2. Since I have 2 blacks 1 white 1 blue. My old O2 was the same but it got super f'd up and I don't know how the wires went.
So I don't just need to know what color is heater and ground etc I also need to know which black goes with what.
 

pcb

The Diagram Dude
V
2002 mazda protege 5
I took a couple of pictures.







The white wire goes to orange and blue goes to yellow.

I'm pretty sure the black wires are ground and doesn't matter which way they go or they would have color coded them differently.
 
V
Mazda P5
Thanks man I appreciate it. I'll plug it up later and see if the engine light turns off. Or if I blow a fuse then I'll reverse the black wires
 
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pcb

The Diagram Dude
V
2002 mazda protege 5
I don't think it would kill the engine if you wired it wrong but you'd probably get a bunch of codes and your car would go into limp mode.

You could possibly wreck your O2 sensor if you connected that to the heater wire. (but I'm not sure)
 

pcb

The Diagram Dude
V
2002 mazda protege 5
I'm rethinking whether or not the black wires are both ground.





One black wire goes to ground in the ECU and the other goes to a transistor in the ECU.

Pins #91 & #93.

I don't know whether or not there will be any damage to the sensor or ECU of you reverse them though.

You could check the terminals on the harness side of the connector with an ohmmeter (car off key out) to help find the right wire.
 
V
protege5
We don't know what kind of sensor it is, sometimes the generic ones use their own wiring colors.

However, usually on any o2 sensor, if 2 wires are the same color, those are the heater wires. It should not make any difference which one goes where.

You'll want to find out about the other 2 wires though. One is ground and one is signal to the computer.

Toyota, Honda both use Denso sensors. On those, I know for certain that Blue is signal, White is ground, and the 2 black wires are heater wires.
 
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pcb

The Diagram Dude
V
2002 mazda protege 5
^^^ What he said.
I was thinking the two black wires would be ground but I went out to check the connector again and the two black wires line up with C & D in the connector which are the heater wires.

 
V
protege5
If the ground and signal wires were mixed up, you'd have a check engine light.

polarity on the 2 heater wires does not matter.


You should be fine if you don't have any blown fuses or check engine light. :)
 

pcb

The Diagram Dude
V
2002 mazda protege 5
The CEL will probably turn off on it's own or you could clear it with a reader or you could disconnect the battery for ten minutes (but you'll lose all your settings in the ECU).

Meanwhile, your car will be in limp mode so clearing the code is a good idea.
 
V
protege5
The CEL will probably turn off on it's own or you could clear it with a reader or you could disconnect the battery for ten minutes (but you'll lose all your settings in the ECU).

Meanwhile, your car will be in limp mode so clearing the code is a good idea.
I've never heard of a car going into limp mode because of an O2 sensor before. Just an annoying light...
 

pcb

The Diagram Dude
V
2002 mazda protege 5
I've never heard of a car going into limp mode because of an O2 sensor before. Just an annoying light...
I might be mistaken but I remember "Install shield"
talking about it years ago.

He did say that when it is in limp mode it floods the engine with fuel and reduces timing advance so your car is gutless and wastes gas.

I suppose I could unplug my connector and see if I notice a difference.

Can a code reader that reads PIDs and freeze frame data determine if your car is in limp mode ??
 
V
Mazda P5
It did run like crap when it got busted,I could feel it when I let off the gas. But it seems to be driving better now once I put the O2 on. But I do need to buy a obd2 scanner though
 

pcb

The Diagram Dude
V
2002 mazda protege 5
Get one of these and download the free torque app.
Make sure you get the one for android or iPhone.
Some are WiFi, some are Bluetooth.

 
V
Mazda P5
Hey just because I bought a Chinese scooter doesn't mean I like all my electronics from China. Haha
I seen those, I'll see what peaks my interest.
 

pcb

The Diagram Dude
V
2002 mazda protege 5
The ELM 327 code reader with the torque app will show you all the input data from all your sensors and display it for you on your phone.

It can also read and rub any code.

I have both kinds but the red one doesn't show sensor data. (and it was $58. )

 

pcb

The Diagram Dude
V
2002 mazda protege 5
The torque app with the reader can show you stuff like this.
It's even got an accelerometer !!



You can mount the phone or tablet to your dash and have realtime gauges.
 

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