elantra 2010 tach wire and compustar

I am doing rs compustar Pro P2W9000FM-AS for Hyundai Elantra 2010 (Canadian version). I have the problem of finding the tach wire. According to this page https://www.the12volt.com/installbay/forum_posts.asp~TID~121915 , the tach wire is:
RED to BLUE/RED (AC) in PASSENGER KICK PANEL, (GRAY, 39-PIN PLUG), PIN 5 .
However, at pin 5, there is a yellow wire. When measuring the wire with a multimeter, it gives 33 to 34 volt AC when engine running and 0 when stop.
My question is why the voltage so high? I also measure the coil and it gives the same voltage ( 0 when engine not running, 4-6 volt AC when turn key to ON position and 33-34 volt AC when running).

I try to do a tach learning, but it does not learn and parking light flash 3 times (no tach signal).

So anyone has any ideal why? Thanks

Use the coil instead or one of the uncommon injector wires.

-------------
Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

Right now I use a uncommon injector wire for tach but it overcranks the engine. I try all combination of options in Tach Sensing Method and Engine Sensing. But result is still over-crank. So I end up to use the last option: no Tach connection and 1.5 second crank.

Also I try tach learning but it fails when option is set to "Tach" in Engine Sensing option and for the "Alternator" option, the tach learning is OK but over-crank.

Is there any way to have the tach connection and not over-crank the engine?

Is the yellow wire is the Tach wire?

Thanks for your reply?

What do you mean by "over cranking" that it cranks for too long? Then either shorten crank time via programming or set tach with engine idling at a faster speed, try 1200 rpm.

-------------
Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

I meant the RS still crank for 2 seconds even the engine already runs.

Finally, I got it fixed. there are 2 wires in injector and I connected to a wrong one. So I switch to the other wire which gives me a lower voltage. The Tach learning is now working. Overcrank problem is gone.

Thanks for you help.

Yes it still cranks even through the engine already running. It over-crandks about 2 seconds or more.

I try to set the "Crank Time" option to "-0.2 seconds to crank time" (setting 4 and only option to reduce crank time?)but it does not make any different. This is the only setting to reduce crank time for compustar? There are other options in tach sensing method but I don't know what they really do. "Previous Tach Method" and "Low Threshold Tach Medthod" but I try them all and it still over-cranks.

How do I set the engine idle at a faster speed? or is there any other way?

Thanks

Foot on throttle!

-------------
Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.