4age bt ox sensor wire has no home

[magweal]

Hopefully ths all I have left nd the wiring is sorted. Its the wire that goes to the body harness, but as the conversion I've done is into a nz new ae101 there's no home for it, does anyone know what it runs to open circut relay maybe???

[Grrrrrrr!]

O2 sensor goes back to ECU, look for a pin labelled O2 or Lambda in the wiring diagram. Also goes to diagnostic port. Can't think of anywhere else it'd be wired to.

[magweal]

There's 4 wires I have a home for 3 2 go to the ecu and I remember where the 3rd went. The 1 need 2 know did go the body harness but I gotta make 1 plug outta 2 coz nz new only had 1 plug from the engine loom 2 body harness

[sergei]

4 Wire Ox sensor has following wires:
Signal
Signal ground
Heater
Heater ground.

Heater goes to IGN wire (switched 12V - IGN key position)
Heater ground goes to normal ground (white with black stripe, bolted on chassis in various places).
Signal goes to ECU.
Signal ground goes to ECU signal ground (brown, bolted on-to on passenger side of the stereo/dash chassis).

Free to correct me if I am wrong (above is from memory)

[matt dunn]

Free to correct me if I am wrong (above is from memory)

I would not be so sure you are correct.
Not sure if it is modern enough,
but most cars with 4 wire O2 sensors have the ECU earth the heater circuit too so that it can sense the current flow and make sure the heater circuit still works.

edit

yes the oxygen sensor heater wires are
one to ign positive
and one to the HT terminal in the ecu,

and the signal wires go to OX and E1.

[magweal]

Ok kool so the wire would plug in with the +B into the ecu? ?

[sergei]

Ok kool so the wire would plug in with the +B into the ecu? ?

+B is the permanent 12V supply for ECU (comes off 15A EFI fuse).

[matt dunn]

+B is the permanent 12V supply for ECU (comes off 15A EFI fuse).

You would think that but you are wrong again, lol.

BATT is the batt feed to the ECU,
+B is the ignswitched feed and is the correct one to connect to.

[sergei]

+B is the permanent 12V supply for ECU (comes off 15A EFI fuse).

You would think that but you are wrong again, lol.

BATT is the batt feed to the ECU,
+B is the ignswitched feed and is the correct one to connect to.

Damn, I am getting rusty lately .
Haven't done rewiring in a while.

Yeah, you are correct, it is likely to be black wire with red or orange stripe.

Looking at silvertop ECU diagram (which should be similar to blacktop in terms of where the OX sensor is connected) here how I see it:

On OX sensor:
Pin 1: Heater connect to HT pin on ECU
Pin 2: +12 Feed for heater, connects to +B in loom (in diagram it is connected to same feed as +B in diagnostic connector).
Pin 3: OX sensor signal connects to OX pin on ECU
Pin 4: OX signal LOW connects OXL1 on ECU

EDIT: Looking at pinout for BT 20V it does not have Pin on ECU for OX ground, so just hook it up to sensor ground.

http://www.club4ag.com/faq_and_tech_pages/Tech%20Photos/AE101_4A-GE_20V_ECUc.jpg

[magweal]

Ok kool that should help thanks Does anyone no what switch on the side of the ignition barrel does

[matt dunn]

Ok kool that should help thanks Does anyone no what switch on the side of the ignition barrel does

If you mean the whuit plastic piece on the side of the ign barrel with two wires coming out of it,

then is is the sensor for the "key in" beeper that beeps when the door is open and the key is in the ignition but not switched on so you dont lock the keys in the car.

Usually just unplug them and leave the that way as they are a PITA.

[CelicaGT8]

Prob also goes to cir relay