OK guys, I see alot of questions and problems with Primary O2 wiring.
This thread will show you the correct info to check your conversion harness if you are having problems. This should help out several members. This little pic is the wire side of the primary O2 sensor plug. Clip is above the 1 & 2 positions. Pins & plug facing away. Wires coming out towards you.
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1 2
3 4
The 4 wires on the Primary O2 need to go to:
1 - Primary O2 Signal (+) (white / red on my harness)
Continuity to C101 pin 19, from there the wire goes back over to ecu A6 where it delivers signal info to the ecu.
2 - Primary O2 Ground (-) (green / blue on my harness)
Continuity to C101 pin 13, from there the wire goes over to ecu A16 which is a sensor ground.
3 - Primary O2 Heater Signal (+) (yellow / black on my harness)
Continuity to C101 pin 15 (from there the wire goes over to ecu A22)
*NOTE: This wire is also divided and is tied into a relay. I will add the relay information a little later.
4 - Primary O2 Heater Ground (-) (orange / blue on my harness)
Continuity to C101 pin 10 (from there the wire goes over to ecu pin A1)
However In some swap harnesses I have seen this wire pinned directly to K-series ecu pin E4. That also works as an appropriate heater ground.
*NOTE: 1 & 2 MUST be wired to the above correct locations for KPro to properly read and display the A/F readings.
*NOTE: 3 & 4 Can be reversed. The heater will still operate without any problem.
This thread will show you the correct info to check your conversion harness if you are having problems. This should help out several members. This little pic is the wire side of the primary O2 sensor plug. Clip is above the 1 & 2 positions. Pins & plug facing away. Wires coming out towards you.
1 2
3 4
The 4 wires on the Primary O2 need to go to:
1 - Primary O2 Signal (+) (white / red on my harness)
Continuity to C101 pin 19, from there the wire goes back over to ecu A6 where it delivers signal info to the ecu.
2 - Primary O2 Ground (-) (green / blue on my harness)
Continuity to C101 pin 13, from there the wire goes over to ecu A16 which is a sensor ground.
3 - Primary O2 Heater Signal (+) (yellow / black on my harness)
Continuity to C101 pin 15 (from there the wire goes over to ecu A22)
*NOTE: This wire is also divided and is tied into a relay. I will add the relay information a little later.
4 - Primary O2 Heater Ground (-) (orange / blue on my harness)
Continuity to C101 pin 10 (from there the wire goes over to ecu pin A1)
However In some swap harnesses I have seen this wire pinned directly to K-series ecu pin E4. That also works as an appropriate heater ground.
*NOTE: 1 & 2 MUST be wired to the above correct locations for KPro to properly read and display the A/F readings.
*NOTE: 3 & 4 Can be reversed. The heater will still operate without any problem.
