Check Valve Timing (On timing chain)

[EMT with a Yaris]

Hoping anyone here can elaborate on the instructions within the service manual for Checking Valve Timing

My 2010 Toyota Yaris 4 door sedan has had a code on and off (Historic/Permanent) for about 14 month now regarding Retarted Cam Timing (P0012)

The Service Manual Instructions are as-follows (screenshot of page attached to this post aswell)
[Page ES-71][4 - Check Valve Timing (For loose and jumped teeth on timing chain)]

(a) Remove the cylinder head cover.
(b) Turn the crankshaft pulley, and align its groove with the
timing mark "0" on the timing chain cover.
(c) Check that the timing marks on the camshaft timing
sprocket and camshaft timing gear are facing upward as
shown in the illustration.
If not, turn the crankshaft 1 revolution (360°), then align
the marks as above.
OK:
Timing marks on camshaft timing gears are aligned
as shown in the illustration.
(d) Reinstall the cylinder head cover.

Im confused on how you would align the markings? I cant seem to find through the hunderds of pages this service manual instructions on how to adjust the timing chain.

Thanks for any and all of your help !

[NYC-SE]

Have you replaced or tightened your accessory drive belt recently? The reason I ask is that people seem to love prying on the Oil Control Valve (OCV) for the VVTI sytem as a pivot point when they adjust the belt. They wind up unintentionally and unknowingly breaking the OCV internally. This can cause a P0012 code. Start there. Search the forums, I know this issue has been addressed here previously. Good luck.

[EMT with a Yaris]

Yeah ive replaced my belt at least 3 times. When replacing the belt I didn't know that the OCV was located there. When I got this dtc p0012 code that was the first thing I replaced when I actually took some action to fix it. The old one was slightly bent but not damaged from previous belt replacement.

Thanks for the prompt reply!

FYI The car has 172,000 miles on it.

Have you replaced or tightened your accessory drive belt recently? The reason I ask is that people seem to love prying on the Oil Control Valve (OCV) for the VVTI sytem as a pivot point when they adjust the belt. They wind up unintentionally and unknowingly breaking the OCV internally. This can cause a P0012 code. Start there. Search the forums, I know this issue has been addressed here previously. Good luck.

[NYC-SE]

It is highly unlikely that your cam sprocket has jumped a tooth. I would be amazed if that is what actually is causing your MIL. Far more likely it is a sensor issue.

[EMT with a Yaris]

I'll go ahead and replace the camshaft position sensor within the week and see what happens. Thanks !

[NYC-SE]

Before you go replacing things do a thorough check of all wiring, connectors, etc. Sometimes just a little moisture or dirt at a connector can cause problems.

[NYC-SE]

I know you said that you replaced the OCV. There is a screen filter behind the OCV that can get clogged and cause problems. Was that cleaned?

[EMT with a Yaris]

Ill do a visual inspection prior to any replacing. I replaced the OCV but didn't know how to remove the screen, Ill check the service manual for those instructions if I can find it.

Currently the P0012 faul is set as "Historic" and not "Permanent"

[NYC-SE]

Currently the P0012 faul is set as "Historic" and not "Permanent"

Before doing anything else clear the code and see if it comes back.

[EMT with a Yaris]

Correct I have done that a few times. Still currently historic. Going to inspect vehicle while I change out the brakes and rotors. But seems like the wheel is all the way rusted on.