Alright, so I'm putting my remote start system in on my 98 240sx, the alarm I have is a Viper 791.

Heres the problem: It'll attempt to crank 3 times, about the second or third time, it'll catch, and the car will start. I tried to set crank to the two-chirp setting, but I don't think it's working. Currently it's at 0.6 seconds.

Second: I'm NOT sure if I've got the right wire for tach. The purple/white wire is supposed to be connected to tach, which is the yellow/red wire in the passenger ECM, so my wiring diagram tells me, when I tested it, it read 12v when the car started. I tried getting the revs up, and seeing if the voltage went up slightly, but it didn't. So instead of setting it to tach, I set it to sense voltage.

Everything works, just want to set it to check off the tach instead of voltage...I couldn't even set the alarm to learn tach b/c I really don't know if I've got the right wire. Instead of stripping them all back and testing individually, I figure I'd ask you guys, see if anyone knew which wire it was...

Thanks!

 

there is probably more than one yellow/red wire in that harness. When I did the system in my 92, which is yellow and black, there were like 4 different wires. Before you tap into any more, test them first. the wire shoud read 0v when off, low voltage when running, and increase with the rpms. it will probably suck ***, but dig through the whole mess of wires going into the ecu.

 

Alrighty, it got dark yesterday so I'm going to get back at it this morning. Wish I had the Snap-on clamps though, they have the "bed of nails". so you don't have to strip the wires back. Thanks though, I'm going to keep looking.

Do you think that I can pull the gauge cluster out, and tap in a wire from there?

 

Ah HAAAA, I think I got it working now. You were right, there were two wires, read 3v, then up to 6 when I reved a bit. It's working now though.

Another question though: Is the car SUPPOSED to learn tach? What if I didn't have to program it to learn tach? Everything works, just wondering why I didn't have to...

 

you can go into programming and program the tach if you want... the good thing i have found with working with viper/sidewinder/hornet (all dei products except for the newer clifford stuff) is that a lot of times you wont have to learn the tach... it will grab it automatically and run just fine... as long as there is no over cranking of the starter ( the starter still spins for a second or 2 after the car is started) then everything should be fine... but like i said if you are worried about it then go and reprogram it with learning the tach and you are all set...

just a little hint on testing the tach wire... set your volt meter on AC voltage... only the tach wire will have voltage and will go up as the rpms go up... saves you from having to change the tach beacuse you know it is the right wire...

 

Ah, thanks! I got it to learn tach, even though it didn't need to, the light lit up though indicating tach was learned. How is it that you can tell if the starter is over cranking? Is it just a noise you hear, like when you do it manually with the key, or what? When I remote start my car, I almost feel as if it doesn't crank long enough, just BARELY to get it started. I tried to change it to the two chirp setting, but I set it back today. Was just curious about that...

Also, I used to drive an Integra, and I didn't install the alarm system at the time, it was a 790, but the same way I could activate the remote start was the same way I could turn it off(lock/unlock at the same time). Doesn't seem like I can turn it off this way with the 791. Did I do something wrong?

Other than that, everythings great, my car is put back together, just hope I don't leave it in gear. I never do...but who knows...

 

the arm and disarm buttons are the same button... the reason for this is that your second channel is used for other options... like trunk pop... and then the third chanel is for the remot start... it used to be button one arms and dis arms... button 2 would be your trunk pop and both button 1 and 2 for remote start... with the new systems i dont know if it still the same i have not installed for 2 years...but it is wired right in any case... good job...

 

Ah, thats good to know...hehe! Thanks for the help. I'm pretty happy with the way things turned out.