P0519 questions

[yohy]

Folks, for the third time in the last few months, the check engine light came on with a code of P0519. Now, I know the code and the FSM steps to track down the issues plus I have searched all of the various forums for input. Questions: the last time it happened, I found a post with a response from a Subaru factory trained technician (with like 7,000 posts) who said “when he gets the code, instead of guessing, he just replaces…and this is where my memory fails me. I figure he says just to replace the IACV but for the life of me, I can not find that post or remember what he said. Anyone remember the post or can steer me to it? From there, has anyone had any success in diagnosing/repair this code as I have checked all of the obvious and the last thing will be to pull and clean the IACV?

 

Second, the car is a ’04 Forester X with 51,000 miles, does anyone know if this is covered under the Powertrain Limited Warranty Coverage: 5 Years / 60,000 Miles or the Federal Specification Emissions Extended Defect Warranty Coverage: 8 Years / 80,000 Miles.

[sea#3]

Asuming it is a manual trany , you would need to replace the neutral switch on the side of the transmission ,

What is hapening is the ECM doesn't know if you are in gear or not , so if you down shift and the revs go up it thinks the IAC is not doing it's job of adjusting the idle and sets the code

 

It probably won't be covered under the drive train warranty but it 's not that expensive to fix

 

SEA#3

[EVOthis]

+1 ^ sea#3....i saw this for the first time the other day at work.......took me forever to find the problem.....

[yohy]

Guys, thanks for the quick replies. Now sea#3, you are correct, it is a manual, but curious if your advice is from experience as the FSM diagnostic procedure (attached) doesn’t mention this at all as it focuses mainly on the air intake system. EVOthis, when you mention you saw this for the first time yesterday, you mean a P0519 code caused by a neutral switch? Again, I really appreciate the time to give me your thoughts.

[OB99W]

The definition for code P0519 is "Idle Control System Malfunction (Fail-Safe)".

 

A known cause of the Subaru-specific code P1507 is a failing (often intermittent) neutral switch.

See http://endwrench.com/images/pdfs/DiagTroubSum04.pdf .

The relevancy is that the definition for Subaru P1507 is "Idle Control System Malfunction (Fail-Safe)".

 

You can try to verify the condition of the neutral switch by meter, but as the EndWrench article says, it can be difficult to confirm. I don't know what the Subaru tech with 7,000 posts said, but since the neutral switch isn't very expensive, perhaps he just replaces it when the code comes up.

 

Of course, the cause could still be IAC-related...

[yohy]

OB99W, thank you for explanation, now I get it, same definition for the two codes. Wild stuff, and yes, the neutral switch then has relevance. I will give the check out the switch tomorrow.

 

Again, thanks for your insight.

[sea#3]

yohy ,,I should have been more clear ..

yes you should still go through the flow chart and if everything checks out ok then i would suspect the neutral switch on the side of the trany . If you can find a scan tool that will give you live data on the switch you can put the transmission in gear and watch the on/ off signal while you gentle move the shifter in gear . If not you could try hooking up to the switch with an analog ohm meter and watch the needle for fluctuations while gently moving the shifter in gear . There should be continuity when in gear , open in neutral

 

SEA#3

[EVOthis]

if you have access to a scantool expecially the selectmonitor (im sure others will work to) go to the data display and you can look at tons of parameters...the way i found it was i went down to like idle control system and i jiggled the shifter without putting into gear and putting it into gear and you can see the IAC counts go crazy.....but yes it was a 519 code

[yohy]

EVOthis and sea#3, thanks so much for taking the time to "learn" the new guy. The reason this forum works so well is the input from folks like you. Thanks again.

 

Now EVOthis, you mention having access to a scan tool to watch specific parameters. I do have a scan tool with real time data, but I am not certain if I can view the idle air control system. The following link will give you screen shots of what's available, can you give me some tips on what to look for:

http://obddiagnostics.com/ScrnShot/Winscreen.html

 

Again, thanks for sharing your knowledge.

[EVOthis]

if you can take a look at the neutral switch on the scan tool....you can just move the shifter back and forth not putting it in gear and if the switch is truely bad than it will think it is in gear when it really is not.....

(it will say on the scan tool if the car is in gear or not)...at least on the selectmonitor it does...sorry i cant explain it better...

[yohy]

Guys, finally had a minute to check out the neutral switch position. Now a few questions. Are there any tricks removing the switch from the tranny or is it straightforward? Does it sit above the fluid level? and I would think you would unhook the harness first at the connector, then remove, correct? I figure for under 20 bucks, I will just start with replacing the switch.

 

Again, thanks for your input.

[EVOthis]

very straight forward...i dont really remember the size of wrench im going to say 22mm but im prob. wrong....yes above fluid level...undo sensor connector, undo sensor, replace....about 5 min....you prob. have to jack the car up though....

[yohy]

EVOthis, thanks for the instructions. That's what it looked like, but I am the master of missing the obvious. Thanks again.

[Ken2004LLBean]

I know this is a realllll old thread, but I'm desperate....

I have been fighting a stubborn P0519 code and am at wits end.  Car has an automatic transmission, but I'm wondering if a faulty inhibitor switch could cause the same symptoms?