Renix O2 Relay Wiring

[XJ-Mayhem]

I’m seeing a diagram that shows the O2 relay should have 4 of the 5 pins wired up

My 90 has a 5th wire orange with black that ties into pin 87 and then goes to the connector for the ambient air temp sensor behind the front bumper feeding the over head console.

This seems like an odd place for the sensor to pull power from, so before I cut out the temp sensor from pin 87 I want to make sure I’m not missing something?

Does the O2 rely on this sensor in any way?

 

[Ecomike]

That does not sound like standard Renix wiring. My 87 and I think the 89 Renix all have one O2 sensor and 3 wires. The Orange wire is high amperage or heater wire to the heater in the O2 sensor. It is powered by a relay, that ECU turns on, so 4 wires to it would make sense.

 

[Saudade]

If you haven't cut it yet, it does go there. The OR/BLK does go to the O2 relay. The relay operates the heater element in the O2 sensor. The diagram I have labels the temp sensor on pin 4 (should be 87, the NO pin). Pin 3 (should be 87a, the NC) is OR and goes to the O2 sensor.

Ecomike is right, the O2 sensor itself only has 3 wires.

The temp sensor also shows 3 wires. One to the relay (the OR/BK), the other 2 to the overhead console.

 

[90xj06]

its a very round about way. but the ecu will switch the O2 relay at WOT an send 12v down the OR/BLK to bypass the ballast resistor to the fuel pump giving it a full 12v. why they chose to go through the connector for the ambient temperature sender. no idea.