WB O2 sensor wiring

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jkrueger
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WB O2 sensor wiring

Post by jkrueger »

I have a question on how to wire in my O2 sensor.

MS3X v3.57
AEM 30-4110 WB gauge and sensor

The manual shows that the O2 sensor ground should be wired in with all the other MS sensors. The WB kit from AEM only has 4 wires: 12v, ground, signal, and serial signal. I assume that the ground is for the sensor and the heater in the O2 sensor. Do I want to connect this ground (that is going to have heater current running through it as well) to the other MS sensor grounds?

Thanks

JC
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arran
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Re: WB O2 sensor wiring

Post by arran »

I would not think it a good idea to wire the AEM gauge such that the heater current is running through the MS Sensor ground setup.
The heater current is typically 1 to 3 amps (reference a tech edge page here http://www.wbo2.com/2d1/default.htm).

The instructions for your gauge describe connection to an (AEM) ECU with just an analog input, which seems unusual to me.
Other AEM WBO2 products like the 30-2310 (which I have) include a separate sensor ground.
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jkrueger
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Re: WB O2 sensor wiring

Post by jkrueger »

I agree. I didn't think that was a good idea. I'll just wire the O2 sensor ground to the same spot I wire the MS engine grounds to. Hopefully I won't get too much of a voltage drop.

JC
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nathaninwa
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Re: WB O2 sensor wiring

Post by nathaninwa »

How long of a run is it? Just use a larger wire for the ground and ground to the engine block. On the 4110 it's power ground,

I also run the Aem failsafe wideband along with the 4110. The failsafe has a power ground and dedicated sensor ground to eliminate voltage differences
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Chiburbian
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Re: WB O2 sensor wiring

Post by Chiburbian »

Just for additional info, the new AEM wideband 02 sensors have two grounds. One is for battery, the other is labeled sensor ground. In this case, I would imagine it is perfectly fine to run the sensor ground from the wideband to the sensor ground on the megasquirt.

Anyone care to disagree?
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ffr3247r
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Re: WB O2 sensor wiring

Post by ffr3247r »

I have just gone thru a huge mess with my WB. It's was innovate though. I had my ground wired to sensor ground and I was occasionally getting goofy readings and sometimes error codes. I replaced sensor, recalibrated, built heat shield. I finically moved my ground to engine grounds and as of today all this has stopped.


I say engine ground where you MS box is grounded
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