low or no rpm

I installed a viper 5701 with idatalink ads-al  gm1 into a cadillac deville 2001.  The alarm, locks, trunk work.  The unit tries to remote start but starter never engages.  the onboard diagnostics show low or no rpm.  I have tried a few different settings, but to no avail.  thanks

To what have you wired your tach lead to and have you programmed it?

where are grabbing tach? from the vehicle or the ADS module?Kevin Gerry

Certified Electronics Technician

MECP First Class Installer

Owner/Installer

Classic Car Audio

since 1979

i tried from the vehicle and the datalink

right now i am connected from the rs to an injector wire for tach. 

You can get tach right at the front edge of the driver's carpet, near where your left foot would be, in a white wire in the harness that comes in through the firewall. But an injector should be OK too. 1. Can you program tach to the unit? 2. If you try to enter pit-stop mode, then turn the key to Off and remove the key, does the car stay running?

if your hooked to a tach program it for tach, NOT virtual tach which is default on new vipers i believe and on your green and purple wires to starter wire do you have cars wire cut and green going to key side purple to motor side?if not you need to do this it is for antigrind so wire must be cut, or if antigrind isnt wanted/needed dont use green just tie purple to the cars starter wire

thanks everyone for your help,  i got it going