[rasterman]

The wires are fairly exposed down there... not unheard of to break them or tear them out on rough terrain. All you can do is follow it upstream and tap it to see where it works, replace from there down.

 

[smn]

Is there a fuse for the oxygen sensor on the 2000 OBW with AT? Does anyone have a diagram for the front O2 sensor and this fuse? I'd like to see what else runs off this fuse.

 

[plain OM]

Front and rear sensors are powered from the same source via the "main relay", so if the rear sensor is working properly, it's not a power supply problem.

 

[smn]

Ok, thanks for the clarification. The wiring diagram I did find agrees with what you say. So I've got either a bad wire or the Bosch sensor that says it's an exact fit isn't communicating. I'll get to finding the wire sometime soon, I hope.

 

[cardoc]

Are you using Global OBD II to read the car? Is your wife's car a Subaru? It may be a programming issue with the scanner. Bosch doesn't tend to make bad sensors. Now if someone dropped the box while unpacking and shelving, then its possible a circuit is open in the sensor. What did the box look like?

 

[smn]

The box was in good condition and I still have it and the old sensor. Both give NO DATA on the reader. My wife's vehicle is a Toyota Sienna using the same bluetooth ELM327 code reader.

I used a Bosch widebad A/F sensor, part no. 17018 from a local Advanced Auto store. I changed it out about two weeks ago.

 

[cardoc]

What is the part number on the old sensor? Its stamped in the sensor base.

 

[smn]

It looks like "258007018". And I see "785145 03".

 

[cardoc]

258007018 is a Bosch Lambda sensor but it doesn't cross to another number. Bosch's webpage shows 17018 as the AF sensor for your car with automatic.

PartInformation 17018

.

 

[smn]

So I have the right part but the ECU isn't seeing it. Looks like I've got to see which wire could be bad.

 

[cardoc]

It could be the scanner isn't seeing that PID. Some scanners will not see all the data on a Subaru. Try a different scanner.

It could still be a connection issue or bad AF sensor.

Also, found a recall on the AF sensor. Attached. The part numbers changed, your is apparently an original. The new part number still interchanges to the new one you have. You will have to check your VIN, last 8, with the list.

 

[smn]

Looks like my VIN is included in the table you provided. I created an account with Subaru.com and see that the service has been done for the front a/f sensor.

 

[cardoc]

According to the part number you posted, it hasn't.

 

[smn]

Interesting... I have the correct Bosch part. I have the old part, too. I'll need to verify the wiring before I take it anywhere.

 

[cardoc]

The part number on your old sensor doesn't match the new part number issued by Subaru when the recall was issued.

The part numbers listed for you car now, 17018, is due to the recall. Its the updated sensor. The recall may save you some cash and headache trying to decipher why the scan tool doesn't see the data.

You could leave the new sensor in and drive it. Within 25-30 miles, if the MIL doesn't come on, the ECM sees the sensor and its your scan tool.

 

[smn]

Something tells me we had the sensor changed about 5 years ago... dunno exactly when. I'll have to try and locate the receipt, if it's still around. Still... a few more things to check out. Thanks much for the info and suggestions.