P0030 code

[cameron griffith]

So the CEL and cruise control was flashing, found out it was the O2 sensor so I purchased a new pre-cat oxygen sensor
http://www.ebay.com.au/itm/301750331880?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT#rwid


The code is still P0030. Any help on where I can go for here?

[Surge]

Did you reset the ECU?

Did the CEL go off at least for any length of time?

Do you have a multimeter ?

Apparently you can test:
"You can check the heater for continuity between pins 3 & 4 on the connector. It should be about 5 ohms."

Quoted from here :
http://www.subaruforester.org/vbulletin ... 523?page=1


The ebay ad also mentions how to test if the O2 sensor you bought even works.

I'm guessing they mention that because they get a lot of returns.

Likely a cheaper sensor and not of good quality, possibly DOA.

[cameron griffith]

The ECU got reset and the CEL stayed off until I took it for drive around the block. I've tested it with a multi meter and it looks like it's also a faulty O2 sensor cos I am getting 0 ohms so I'm going to return it.

Is there any other option than buying one from subaru as I don't want to spend a ton

[Surge]

These guys are good :
https://partsouq.com/en/catalog/genuine ... baru+Japan

More options in this thread:

viewtopic.php?f=45&t=34641

[SubaruDIY20]

The ECU got reset and the CEL stayed off until I took it for drive around the block. I've tested it with a multi meter and it looks like it's also a faulty O2 sensor cos I am getting 0 ohms so I'm going to return it.

Is there any other option than buying one from subaru as I don't want to spend a ton

Hey Cameron,
did you end up resolving your P0030 problem? I have the exact same issue as you - CEL comes on due to P0030 code somewhat randomly (possibly on cold days). I replaced the O2 sensor, and it didn't fix the problem.

As a reminder, P0030 is a fault in the control circuit for the heater element of the O2 sensor.

This thread is from 2017, so I might start a new one if this one is cold (no pun intended).

[bigBADbenny]

P0030 for H4DO Legacy 2006 on jdmfsm dot info:

Wiring diagram:
https://jdmfsm.info/Auto/Japan/Subaru/L ... 04336e.pdf

Diagnostic steps:

IMG_2023-07-17-134054.png (255.78 KiB) Viewed 5317 times

Having the complete fsm pdf will be helpful: see the red link in my signature.

Don’t forget to reset the ecu after repairing the fault and or sensor…

[SubaruDIY20]

P0030 for H4DO Legacy 2006 on jdmfsm dot info:

Wiring diagram:
https://jdmfsm.info/Auto/Japan/Subaru/L ... 04336e.pdf

Diagnostic steps:

IMG_2023-07-17-134054.png

Having the complete fsm pdf will be helpful: see the red link in my signature.

Don’t forget to reset the ecu after repairing the fault and or sensor…

Thanks bigBADbenny, I'll see how I go with this!

[bigBADbenny]

Here’s the fsm multimeter tests for the harnesses.
https://www.dropbox.com/sh/6w38xtm9lv5y ... vPTBa?dl=0
You can also search YouTube for continuity, resistance and voltage drop tests, and how to back-probe a harness wire… “the trainer” has my favourite vids…

[SubaruDIY20]

P0030 for H4DO Legacy 2006 on jdmfsm dot info:

Don’t forget to reset the ecu after repairing the fault and or sensor…

Is clearing the fault code using an OBDII scanner and app (Torque lite), the same has resetting the ECU?

[bigBADbenny]

Yes it is the same thing, generally…