Prestige APS57E keeps losing Tach signal

Installed an Prestige APS57E + Fortin bypass on a 2014 Toyota Corolla standard key via D2D. The lock, unlock and trunk functions work with no issues but on more than two separate occasions, the alarm has lost it's tach signal. Both times, it has been after a disconnected the Evo-All to change some program settings and reconnected it (without disconnecting the power from the Prestige). The strange thing is I am getting the Tach signal directly from Pin 9 on the OBDII connector and not via D2D. Everytime it has happened, I simply go through the Tach learning process without touching any connections and it learns perfectly fine. I even started the car four times after for the Crank Averaging procedure. The car usually remote starts fine on a regular. Anyone ever had to go from Tach to Tachless before? Never had this issue with other vehicles I have done.

Interesting problem. Ignoring the fact that disconnecting the EVO-ALL and making changes is not a normal function and most systems that are installed never get disconnected. Wonder if you would lose the Tach during years of use if this disconnect never happened? The EVO-ALL can and does supply a Tach signal via the D2D connection with this application. There is no way to turn it off like you can with iDatalink bypass modules. The APS57E does have programming that allows you select where the Tach signal is coming from. In your case the APS57E should be set to 5th Feature = Tach and not DBI Tach. Might want to check this setting to be sure. Another possibility is going full W2W between the APS57E and EVO-ALL and see what happens. Think there are a few big Prestige users on this Forum, so maybe they have more experience with this issue...Soldering is fun!

I had this issue a few years ago with a Prestige APS687C. I spoke with Audiovox tech services, and the tech suggested to continue holding the programming button down for 10 seconds after the lights begin flashing during tach learn, ensuring that the tach program memory is full. I did this and never had a problem after that point. Now, when I am programming the tach on an Audiovox unit, that is the normal procedure that I follow, and I've had no issues. It wouldn't hurt to try this if the problem surfaces again.Lectric Guy

kreg357 wrote: Interesting problem. Ignoring the fact that disconnecting the EVO-ALL and making changes is not a normal function and most systems that are installed never get disconnected. Wonder if you would lose the Tach during years of use if this disconnect never happened? The EVO-ALL can and does supply a Tach signal via the D2D connection with this application. There is no way to turn it off like you can with iDatalink bypass modules. The APS57E does have programming that allows you select where the Tach signal is coming from. In your case the APS57E should be set to 5th Feature = Tach and not DBI Tach. Might want to check this setting to be sure. Another possibility is going full W2W between the APS57E and EVO-ALL and see what happens.

Normally I never have to mess with a bypass post-install but I was having issues on this vehicle because I enabled the Evo-Alarm feature (the Fortin bypass creates an alarm) but the customer complained of the alarm going of on random occasions after unlocking the car with the OEM key. It never happens when unlocking the car with the Prestige key. After going back and forth with Fortin support, decided to turn it off altogether. I know the Tach option was selected because I wouldn't be able to do the Tach learning process since the Evo-All would be sending an ADS protocol Tach signal and not DBI and I don't believe the Prestige line can do Tach via ADS.

lectricguy wrote: I had this issue a few years ago with a Prestige APS687C. I spoke with Audiovox tech services, and the tech suggested to continue holding the programming button down for 10 seconds after the lights begin flashing during tach learn, ensuring that the tach program memory is full. I did this and never had a problem after that point. Now, when I am programming the tach on an Audiovox unit, that is the normal procedure that I follow, and I've had no issues. It wouldn't hurt to try this if the problem surfaces again.

I actually contacted Audiovox Tech support and a rep. recommended a similar solution. He said he personally allows at least 14 parking light clicks and starts the car four times -- allowing it to run at least 15-30 secs. I will do that next time this happens. Hopefully there isn't a next time.