viper 5904 remote start problem

Hi Everyone. I have searched but I have not found the answer to my issue. I am a former Honda factory certified master technician that specialized in electrical problems when I worked at the dealerships 20 years ago, so I believe I have covered all the basics.. I installed the 5904 in my 91 Honda accord and all works well... except for one strange issue. When I remote start my car, it starts and runs for 10 seconds, with the starter over-rev spinning, then it shuts off. It starts 3 times then sends a "Low battery' to the remote. My idea is the brain is not picking up any signal from the virtual tach and never thinks the motor is running. I am certain that I have all the inputs to the brain hooked up right but I guess I am wrong. I must have hooked at least one wire to something wrong.. so it can not pickup the virtual tack and/or it can't sense any voltage. I have read in other posts to just hook up the tach wire, but how to account for the error " Low battery"? That implys one of the inputs isn't getting any voltage. I am confused and wonder if anyone has any ideas for me to try? I would really appreciate it. Thank You in advance... Oh, let me add I have a DEI backup battery installed. I wonder if it could be masking the voltage surges from the alternator?....old and lovin' it

While this is not the answer you are looking for, most installers will set the remote start

system up to use an actual Tach signal.    The reason is simple, nothing is better thanan engine RPM signal for indicating when the engine is started.  It consistently provides excellent results in all climates.  Virtual Tach is Directed's best effort in guessing how longto crank the starter.  Sometimes it works well and often times it doesn't.  The bonus of goingwith Tach Mode is the Viper's engine over-rev protection during remote start operation.

Setting your Viper to Engine Sensing = Tach ( Menu 3, Item 2, Option 4 ) is pretty easy and

as a mechanic familiar with the '91 Accord you know that a solid Tach signal can be found at the Blue wire at the distributor.  The Viper's Tach Learn process is described in the install guide.  Save yourself some future headaches and switch to Tach Mode.

Soldering is fun!

yes, I can of course hook up the tach wire. I have thought of that and decided if no one ka couple of issues with that though. 1. If the tach wire is disconnected I have this exact problem back. If it is disconnected I may not know it for awhile. 2. Another non-factory wire in the engine compartment just makes it that much easier to find the 3. there is a failure. Either I am misunderstanding the input wiring, or the microprocessor that is deciding the RPM is not working.. or.... The fact that it says " Low Voltage" on the remote implies that I missed an input, or the input is damaged. I hate that, and if I fix this issue, how many others would be happy to know how to make this work reliably. If anyone has any idea which input normally is read by the virtual tach, that would help immensely. I would know where to look. In return If I find a solution that works, I will report it back here, and perhaps help others in the future. Thanks for reading! old and lovin' it

Sorry, the first line in my post was supposed to say I have thought of that and decided if no one knew the answer, I would do it, but I have a couple of issues... old and lovin' it

The low voltage is referring to the strength of the tach signal.  So it sounds to me like you are in tach mode and not on v.tach. You will have to 'zap' the unit and then correctly set v.tach by remote starting the vehicle, wait for parking lights to come on and then shutdown the remote start via the remote.  I've had decent luck with virtual tach on the newer viper systems, but hardwiring your tach wire is certainly still the best way to go about it, and your already running a siren and hood pin in there so what's one more wire...

and when you 'zap' it, it will erase the remotes from the system so they will have to be paired back up.

Hey, that is quite possible. I remember the first attempts to set some of the options using the beep codes. Maybe I went the wrong exit and set this option on. I will test it I have bought a bitwriter to help with the final tuning and I will use it (when it arrives) when I install a similar system into my wifes car. In any event, I really appreciated the knowledge and kindness you showed when you posted this. Thank you very much I may have never thought of this. It is amazing sometimes something can be right in front of you and you mis-construe it as something else.... Thank You old and lovin' it