Hyundai Accent 2015 P0447 Permanent Code: Can It Be Cleared After Remote Starter Installation?

When does the check engine light (CEL) come on during each start? Is the P0447 code listed as pending or permanent in your scanner's memory? It might be a reader issue. If the underlying condition isn't resolved, you cannot erase this type of circuit-related code. Step 1: With the key off and engine off (KOEO), check for 12V at the vent valve. Reference: http://www.obd-codes.com/p0447

The CEL does not come on during driving, but it briefly flashes for a few seconds each time I start the engine—then goes off quickly once idle is reached. The P0447 code is consistently shown as 'permanent' and appears every time I perform a new scan. This suggests it's not just in history mode. I’ve been driving over 100km in the past 24 hours with no recurrence of the CEL. I’m still working to identify the correct purge valve location. The purple wire near the injection harness is from the remote starter, and the red tape marks where my tachometer signal was connected.

The vehicle is under warranty for a 2015 model—why are you handling this issue yourself? Could you confirm whether the CEL activates at each start? And is the P0447 code listed in the pending or history section of your scanner? Note: The image shows the purge valve. The vent valve, however, is located near the charcoal canister at the rear of the vehicle, close to the fuel tank.

Installing aftermarket devices on a brand-new car is generally not recommended—especially when you're modifying factory wiring. Remove the remote starter and see if the P0447 code resolves. If you absolutely need a remote start, have it professionally installed by the dealer. I suspect your warranty may be voided due to unauthorized modifications. Any future electrical issues stemming from this could fall outside coverage.

kev2 wrote: 2015 is under warranty - why are you dealing with this? I asked above - "When you start does the CEL come on at each start?" and also if the code reader was listing the Pending or History list? On every engine start, the CEL flashes for a few seconds before turning off. It never stays lit during operation. The P0447 is labeled as 'permanent' in the scanner—this appears every time I perform a new reading. I don’t believe it’s just a history code. I’ve installed remote starters independently in the past, but this one failed on first attempt. I’ve never had a dealer install such a device due to cost differences—dealers charge twice as much. If an independent garage installing a remote starter on a new vehicle doesn't void the warranty, then why would I? I understand your concern, but I disagree with that assumption.

It sounds like the CEL is active in some way—yet the P0447 isn’t triggering it. That’s confusing. Try this: Clear the code and then drive under normal conditions. If the issue returns, we can move to circuit-level diagnostics. Are you familiar with a digital multimeter (DVOM)? FYI: While independent garages may not void your warranty for remote starter installation on new vehicles, any wiring modifications become the installer’s responsibility. The manufacturer typically reserves rights in such cases. However, if the dealer had performed the work, it would likely be covered under warranty. This is just a general advisory.

Thanks for all the responses and support. I’ve now resolved this issue: I believe the Powertrain Control Module (PCM) requires sufficient data to perform proper diagnostics before clearing codes like P0447. After several days of driving, the code disappeared on its own. I contacted my dealer and explained the situation. They confirmed that the P0447 is covered under warranty because there’s no direct link between the remote starter installation and the fault. I have an appointment tomorrow morning for a full diagnostic check under warranty. For over a week, I’ve been scanning daily to confirm the code remained persistent. Tonight, for the first time, the P0447 is no longer present—indicating it has cleared automatically (likely due to the PCM collecting enough data during drive cycles). Thanks again! Nien

You're absolutely right—the PCM requires specific conditions (such as engine temperature, fuel level, vacuum levels, vehicle speed) to run diagnostic tests. It needs multiple successful test runs before clearing a code like P0447. This is known as a 'drive cycle.' Keep driving under normal conditions and monitor the system closely. Good luck with your new Hyundai Accent!