20 Valve silvertop wiring o2 sensor

[ONCE-NA]

Ok ive searched everywhere but cannot find clear and exact instructions on how to hook up an oxy sensor to a Silvertop ecu.
I have a universal 4 wire sensor with 2 wires for the heating element a ground wire and a sensor output wire.

And there are 3 o2 sensor related pins on the ecu

N8 - HT - Heated oxygen sensor
M6 - OX - Oxygen sensor
M13 -OXL1 - Oxygen sensor

So i'm assuming I should wire one side of the heater element to and ignition switched +12VDC
and is the other side wired to N8 and pulled to ground by the ECU to activate the element?
and should the ground wire of the o2 be wired to a chassis earth or N9 on the ECU (sensor ground)?
and as for the sensor output, M6 or M13?
Or do I have it completely wrong?

[Matt]

12v to the 02 sensor comes from the ecu ht pin. Will confirm the others for you tomorrow if I get a chance

[Nikkojoe]

If its anything like the ae92/ae101 4agze 4 wire 02, the 12V comes from the black red efi main wire and is then earthed out through the brown ecu earth wires. However looking at the ae101 wiring diagram it has the +B input (black red efi main) but it would be safe to say the earth would go straight to the ecu (most likely the HT wire - but check to see if this pin earths when the car is running).

Have a feeling the output would be M6, but not too sure.

[ONCE-NA]

I wasn't getting either +12vdc or switch to earth from the ht pin. Maybe the ecu is more stuffed than I thought...

[Matt]

Nikkojoe is right with the HT pin earthing it, in the conversions i've done the HT pin has always had 12v when i checked it and i assumed it came from the ecu. But looking at the diagram it is shared with the B+ so that explains it.

Wires at the 02 sensor for the silvertop on the engine harness are

Pink/Black stripe - HT
Red/black stripe - OXL1
Black Unshielded wire - +B , also powers the ISCV valve
Black Shielded wire - OX

I got the mulitmeter out and confirmed the pinouts on the ecu are as below...




According to google, OXL1 appears to be oxygen sensor ground, but interestingly enough it has been deleted from the blacktop 20v loom.

Hope this helps.

[ONCE-NA]

I havent got that part of the original loom as it came to me from a dodgy conversion. thats why i need to know what pins on the ecu corraspond to what wires on the o2 sensor

[Matt]

Ahh cool,

HT pin is defo the earth for the heater side of the sensor.
OX is the Signal and i'll trace the oxl1 tonight when i get home as i've got a spare unmolested loom..
OX is also present in the diag box too.

[ONCE-NA]

Okay cool, that would be a great help mate!

[Matt]

Traced and updated original post up above...

Let me know if you need more info.

[ONCE-NA]

thats great! thanks mate!
Its all wired up now.Got the check engine light going too although its showing no codes even when i force errors.
Waiting on another ecu