Can't work out the wiring of oxygen sensor.

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[email protected]
Posts: 106
Joined: Fri Apr 29, 2016 10:33 pm

Can't work out the wiring of oxygen sensor.

Post by [email protected] »

Apparently the wiring on the sensor by Denso
Blue - sensor
White - ground
black - heater
black - heater

I have this image with Black, Red/white, Black/yellow, Brown 4 wires in total
http://imgur.com/7oBbKBR


and this is the actual picture inside my car of the existing denso sensor...
http://imgur.com/J7bCE6N

is this wired up correct? at present it's white to red/white -- blue to black/yellow -- black to black -- black to brown

any help appreciated... also can anyone tell me what OX1 and HT2 and B and E mean?
thomp1983
Posts: 1545
Joined: Sat Oct 01, 2011 1:30 pm
Location: newark, notts

Re: Can't work out the wiring of oxygen sensor.

Post by thomp1983 »

a 4 wire lambda sensor has a heater circuit plus the signal circuit, ox1 is the sensor reading to the ecu and is black on the car loom, ht2 is one half of the heater circuit and is red/white on the car loom, e is the sensor earth wire and is brown on the car loom and b is the other half of the heater circuit and is black/yellow on the car loom.

on your denso sensor you need to wire it
blue to black
white to brown
black to red/white
black to black/yellow

it doesn't matter which way round the blacks are but from what you've wrote yours is wired wrong
[email protected]
Posts: 106
Joined: Fri Apr 29, 2016 10:33 pm

Re: Can't work out the wiring of oxygen sensor.

Post by [email protected] »

Sir you are a legend!

This was a car I bought for cheap of a guy who had no idea. so it doesnt surprise me he wired it up wrong... looks like a brand new sensor aswell!
[email protected]
Posts: 106
Joined: Fri Apr 29, 2016 10:33 pm

Re: Can't work out the wiring of oxygen sensor.

Post by [email protected] »

Yes confirmed!!!!! you saved the day... I have no error code anymore!!!
I reset the ecu and its a healthy engine...

having an oxygen sensor that was wired up wrong would have what effect? possible bad emissions?
thomp1983
Posts: 1545
Joined: Sat Oct 01, 2011 1:30 pm
Location: newark, notts

Re: Can't work out the wiring of oxygen sensor.

Post by thomp1983 »

it would cause the car to overfuel, can potentially damage the cat or cause bore wash but most likely everything is fine
[email protected]
Posts: 106
Joined: Fri Apr 29, 2016 10:33 pm

Re: Can't work out the wiring of oxygen sensor.

Post by [email protected] »

good news we fixed the sensor as I just put a new cat on yesterday!
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