Error code P3700

Hi fellow legacy owners,

I recently bought a used legacy with the motor lamp on. A quick scan revealed a P3200 error which lead to a defective upper O2 sensor. I measured the old sensor and it had infinite resistance in the heater circuit. Also i had no output on Bank 1 Sensor 1. So i replaced the faulty sensor and deleted the error. Now after a few miles i get a new error P3700. There is still no signal showing up on Bank 1 Sensor 1. Bank 1 Sensor 2 is working fine.

Maybe you have an idea an can help me ?

Cheers!

https://legacygt.com/forums/showthread.php/trouble-codes-cels-26113.html

I don't see that code listed there.

The service manual may help,

http://people.csail.mit.edu/ilh/vacation/

Doomy, where are you located and what year/model/trim legacy are you working on?

That will help with troubleshooting.

Thank you for your replys.

It must be a manufacturer specific error. I'm located in Europe(Switzerland) and its a 2.0R 2006 BP5(Station Wagon) with 165Hp

How are you reading the code off the car?

I'm looking at the EU shop manual and the highest DTC Subaru lists is ~P2500

P3700 is a generic error code, not a Subaru specific code.

Do you have any way of pulling the Subaru DTC?

Thank you Infosecdad.

I'm using a cheap chinese obd2/bluetooth adapter with android torque app.

Sadly a dont have access to a good reader. I will probably have to bring the car to a subaru dealer.

What year is the car? It may be a good time to get a cheap vagcom cable or get the btssm app. Your Bluetooth adapter may be able to connect to the app.

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Not sure if this will work for you but worth a try.

Tried both, the btssm app did not want to connect with the ELM327 adapter and i could only make S-on and S-off apear in the trip meter.

Will order a vagcom off ebay. Did some more tests today and i can only see a signal from Bank 1 Sensor 2, there is still no signal showing up on Bank 1 Sensor 1. It also looks that the cat is not working right, the signal of the downstream sensor fluctuates between 0.1 and 0.9.

Tried both, the btssm app did not want to connect with the ELM327 adapter and i could only make S-on and S-off apear in the trip meter.

 

 

 

Will order a vagcom off ebay. Did some more tests today and i can only see a signal from Bank 1 Sensor 2, there is still no signal showing up on Bank 1 Sensor 1. It also looks that the cat is not working right, the signal of the downstream sensor fluctuates between 0.1 and 0.9.

Sent from my SM-G970U using Tapatalk

Ah yeah i thought i was because of the cheap module. Could be that Bank 1 Sensor 1 is not showing anything because of the ELM327. Same for the error codes.

Im going to order a vagcom. This does probably not work with SSM, is there a cheap cable that does?

Maybe this one?

https://www.aliexpress.com/item/32810481841.html?spm=a2g0o.productlist.0.0.15ba53ddlHMbFA&algo_pvid=c9fa49ad-e220-4cff-8596-4a9b574cb8b6&algo_expid=c9fa49ad-e220-4cff-8596-4a9b574cb8b6-0&btsid=0ab6f82315898066473171974e6d41&ws_ab_test=searchweb0_0,searchweb201602_,searchweb201603_

Ah yeah i thought i was because of the cheap module. Could be that Bank 1 Sensor 1 is not showing anything because of the ELM327. Same for the error codes.

 

Im going to order a vagcom. This does probably not work with SSM, is there a cheap cable that does?

 

Maybe this one?

 

https://www.aliexpress.com/item/32810481841.html?spm=a2g0o.productlist.0.0.15ba53ddlHMbFA&algo_pvid=c9fa49ad-e220-4cff-8596-4a9b574cb8b6&algo_expid=c9fa49ad-e220-4cff-8596-4a9b574cb8b6-0&btsid=0ab6f82315898066473171974e6d41&ws_ab_test=searchweb0_0,searchweb201602_,searchweb201603_

Someone made alot of them and they are sold all over the place pretty cheap but they should work with all the logging software

Sent from my SM-G970U using Tapatalk