Technical Information Euro Civic Type R Wideband O2 Wiring


This information applies to a non-US vehicle, so Hondata does not have the facilities to diagnose and troubleshoot any issues with the following information. This information is supplied 'as-is' and is unsupported by Hondata. Contact your European dealer with any questions.


The European Civic Type R uses a narrowband front oxygen sensor. The ECUs for the US and Japanese K20 engine equivalent all use a 4 wire wideband which reads from 11.5 to 20:1 air fuel ratio. If you want to run with a wideband for more accurate in car tuning, you must use the PRB, PRC or PRD ECU together with the oxygen sensor part number 36531-PRB-A01.

Wiring diagram

The first diagram is from a stock Civic Type R with narrowband oxygen sensor. The second shows the changes necessary to run the US ECU and oxygen sensor. Click pictures to enlarge.

This diagram is the intellectual property of Hondata and may not be reproduced elsewhere.


- Remove the pink wire from connector E4 (signal ground 3) and connect to A16 (Primary Heated Oxygen sensor - ). This is best done with an AMP pin removal tool. A16 is unused on the UK Civic Type R harness.

- Unplug the rear oxygen sensor and disable OBDII in K-Manager.

- Connect A22 (use a T-Tap) which is unused on the UK Civic Type R harness to A2. This provides a switched 12V to the ECU to tell it that the oxygen sensor heater is receiving 12V and working.


The front wideband O2 sensor works by measuring current flow, not voltage.

Connector E4 grounds both the front and rear oxygen sensors. If you wish to continue running the rear 02 sensor you will need to run another wire from E4 to ground it. The rear O2 is used only for measuring catalytic converter efficiency.

The wiring changes above will not enable the ECU to detect when front O2 heater is not functional. It assumes it is always working. If your heater fails your O2 sensor may fail to respond or respond slowly.