What kind of tach signal does the factory tach need to see?

[Janz99]

Hey guys, Im looking to temporarily hook up my factory tach, but I need to feed it a tach signal from my aem. So my question is, what type of signal does the factory tach need to see? Right now my AEM is setup for COPS configured in wasted spark. I still have to look into what type of signal the aem can output, so ill have a look at that next to determine if this is even possible or not right now.

Just a side note, I have zero factory wiring in the car right now, its all completely new. Car is 2j swapped running on an aem v1 right now.

 

[NashMan]

just runs of ground signale form any one of the coils you choose

 

[IJ.]

5v square wave from memory.

 

[NashMan]

ps there auto config in aem just go in setup wizard if remmeber right


http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=D&P=6

http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=BE&P=39

reataces levels

 

[scubajtw]

Sorry to bump a dead thread but did you ever get the factory tach to work with a signal from the AEM? I am running 1zz-fe COP with built in ignitors and v2 on my 7m. So there is no output from the ignitor other then the 6 individual IGF signals at the coils.

 

[scubajtw]

Never mind the last post the output signal from the AEM default is a good signal for the tach.

 

[Orion ZyGarian]

Never mind the last post the output signal from the AEM default is a good signal for the tach.

Good to know, thanks for posting an answer so that years later, people will find this thread AND their answer instead of just the thread

 

[scubajtw]

No problem. One thing I ended up doing was running the ig signal wire at the datalink connector and the tach wire also there sincey wiring is far from stock and has a lot of loose wire tied up differently. When I have time I will see if I can figure it out for the v1 7m plug and play.

 

[IJ.]

Have you checked to see how accurate it is on the AEM?

Mine on the standalone was all over the place above 5000rpm.