2006 V70 2.5T pulled code P0036

obayha · Post by **obayha** » 02 Aug 2015, 14:24

Something Is Going on with the O2, but the read out in saying.
1. Check circuit fuse. Checked OK
2. Relay defective. Where is this and how to check?
3. Check circuit wiring. Where to start on this?

Any help would be great. Didn't see much in the forum.

Post by **DGM** » 03 Aug 2015, 04:22

I found the following wiring diagram for you. Basically if you read battery voltage on fuse 11B/14, the relay FMA3 (unit 2/32) isn't a concern. The unit 7/15 is the front oxygen sensor, the unit 7/82 is the rear. As per obd code P0036, you experience a problem with the heating element circuit on the rear sensor.

You can verify that you have battery voltage at pin #1 when rear sensor connector is open (green/brown wire). If present, most likely the heating element of the sensor is defective/open. If not trace accordingly.

Have fun...

obayha · Post by **obayha** » 03 Aug 2015, 06:49

As wife was driving to store yesterday, noticed something hanging down from car. Forgot about it till this morning. It's wires. So I assume something has come loose and causing the problem, or my local groundhog mechanic has been working on the wrong car. Will check it out after work today.
Thanks for the diagram. It will come in handy.
Shane

obayha · Post by **obayha** » 03 Aug 2015, 18:41

Here's what I found tonight. The Walmart bag was melted to the cat and you can see what a mess the wires are.
Are there any major problems driving the car about 70 miles tomorrow. Misses has appointment and wants an answer from someone other than me.
Will it shut off or just run a little different?
Shane

obayha · Post by **obayha** » 03 Aug 2015, 18:49

Would it be a good idea to rewire?
And are the white wires the same?

Post by **DGM** » 04 Aug 2015, 07:24

Would it be a good idea to rewire?

Yes depending of your skill to solder new wires with heat shrinks. Most will simply replace the sensor at this point.

And are the white wires the same?

They are the heating element. No particular polarity on them.

However with the other two wires you must respect polarity.

I suggest not to run for long without the sensor connected. At least not with the hole unplugged (exhaust leak). The rear sensor is there to monitor CC efficiency.

Hopes this help,

obayha · Post by **obayha** » 04 Aug 2015, 13:18

Thanks for the reply. Working on the rewire today. Hope it warms up a little. Not quite 100 yet.
Anyone know the nut size, before I crawl under there?
Shane

Post by **DGM** » 04 Aug 2015, 15:45

7/8 will do.

obayha · Post by **obayha** » 05 Aug 2015, 08:03

One more question. Will the CEL reset it's self or do I need to do the battery removal?
Could not budge the O2 sensor, so I work with everything under the car. Not my best work, but we will see what happens.

Post by **abscate** » 07 Aug 2015, 06:38

Removing the battery negative terminal for 10 minutes (have your radio code handy) will reset the CEL.

How old is your O2 Sensor? It might be time to replace it anyhow.