Honestly I have searched Internet a Lot and could not find one example related to Honda City 2006 I-DSi which can help me configure the problem. Problem turned into difficult because I could have identified the wires of O2 sensor but had no knowledge about the incoming wires from the ECU because of missing grip. Wires from ECU had completely different color combinations from that of sensors which has one Grey wire, One Black wire and two white wires. I read many blogs where everyone said that every manufacturer uses different color combinations of wire from ECU which is different in every model and this looked more like a Marketing strategy of Car Manufactures where they want Honda owner to turn to them for repairs. I also could not find a single article or Manuel which can explain the wiring diagram of Honda City 2006.
I had a missing Male grip from Sensor and Available Female grip from ECU to the sensor. This sensor was located on lower back side of Engine so I found it a very difficult approach. Company charges Rs 20,000 for this new sensor where as I think it is a Universal 4 wire Platinum/Zirconium O2 sensor with only thing different is the GRIP. They are manufactured by Third part company which is sold in much lower price but Honda has added its own GRIP on this to make it specific to their cars & model. Number of threads I came across where people have explained that they bought a universal GRIP along with Male and Female GRIP and successfully integrated this with their cars.
Color combination of 4 wire O2 sensor for Honda City are black, grey, white and again white. These two white wires are meant for sensors heater where as grey wire is sensor ground and black wire is signal to ECU. I have measured the resistance between two white wires which turned out to be 6.75 OHMS. Then again found the same resistance once I flipped the Multi meter on the white wires. Then I bought the long small wires and connected it to Cars ECU wires to O2 sensor through Female connector in order to measure the Voltage from ECU to find the right match. Here I could not read the wire colors due to light problem but have identified it this way.
Picture of Female Connector from ECU looks like this
A) Multimeter connected across (4,2) 4 is positive polarity and 2 is negative polarity
B) Potential different between 4 and 2 was 8Volts
C) Multimeter connected across (3,1) 3 has positive polarity and 1 had negative polarity
D) Potential difference between (3,1) was 0.05 Volts
E) 4 was connected to negative terminal of battery via Multimeter and the potential difference was 13.8 Volts
F) 2 was connected with Positive terminal of Battery Via Multimeter and the potential difference was 8 Volts.
G) Polarity between ( 1,2) was 1 negative and 2 positive
H) Potential difference between (2,1) was 0.20 Volts
I) Polarity between (3,4) was 3 negative and 4 positive
J) Potential difference between (4,3) was 13.8 volts
Probably because battery was fully charged and car was on once these measurements were taken.
1) My guess is that (4,3) is for two white wires for heaters
2) 2 is for black heater wire which is a signal from ECU
3) 1 is for grey wire from O2 sensor which is ground.
What do you say