Code 41 primary oxygen sensor heater


civicx3

Drop a gear & disappear!
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Jul 22, 2009
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Can anyone help with code 41 on the engine management light which is primary oxygen sensor heater.

The car is obd2 and the engine is obd1 so do i need to do the single wire 02 sensor to 4 wire conversion? If so do you run wires from the 02 sensor to the ecu or somewhere on the loom??

Need to know if just need a new 02 sensor or if i need to do this conversion as i want this management light off

Couple of links here but cant work it out

https://honda-tech.com/forums/honda...gine-swap-wiring-guide-vtec-non-vtec-2987229/

https://honda-tech.com/forums/tech-misc-15/wiring-4-wire-o2-sensor-1-wire-harness-334989/

Cheers
 
figured it out using those links, for anyone else in the same boat...

"If you bought a CX or DX civic with a 1-wire o2 sensor, you're going to have to convert to a 4-wire to run a b-seires ecu, and most of the "top of the line" d-series ecu's like the p28.

First things first, you need to physically buy a 4-wire o2 sensor. you can't send a heater signal to a device which has no heater circuitry and expect it to work


Wires on 4 wire O2:

WHITE: Signal Wire
GREEN: Signal Ground
2 BLACK: Both black wires are the heater circuit wires.

Using a P28 ECU (and should work for most obd1 ecu's with 4-wire controls)

Run O2 Sensor signal (white) To D14
Run O2 Sensor signal Ground (green) to D22 (or any good Ground)
Run O2 Sensor Heater Circuit Control (black) to A6
Run the other black heater circuit power wire to (A25) or any good switched +12VDC source.

(you may mix up the black wires... if car dies after it is warm/10-30 seconds, that's the first thing to swap over and troubleshoot.. theres no way to tell one from the other by looking at them) "

80-img_3590_b14537d0a1990f6601f556e823ed5da5297c2760.jpg
 
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