Viper alarm issues.

[Don-T]

I am having a problem with a Viper 791XV alarm system in my truck. The installer setup the remote start to crank for . 8 seconds and not check the engine. This means that the alarm assumes the engine started but has no way of knowing. They claim this is the only way to do it. There is a tach input to the alarm that I tied into the injector for #1 cylinder. The alarm is programmed to see the tach input but when I do a remote start using the tach input the starter does not stop spinning. The way it is programmed it should stop spinning when it gets the tach signal. I tried to talk to DEI about this and all I get from them is “You must go to your installer and have them fix it. ” I have tried that two times, there is no point in going back. If I go to another installer they will charge me to look at it and I don’t want to pay again. Has anyone had any experience with this?



Another issue I have is that when the engine is running via remote start the fan for the HVAC system works but the AC clutch does not engage. I looked through FSM but I don’t see a way to make the AC clutch engage and be able to cycle on and off as needed.

 

[Don-T]

Anyone have a DEI alarm with remote start?

 

[JKloppe]

I have the clifford 3. 5rx and it works great. Viper and clifford are the same company, So it should work. I will check with my brother to see what needs to be done with yours. He is the manager of install at Soundtrack. I will get back with you.

 

[Don-T]

JKloppe, thanks for the response. I hope your brother can shed some light on this.

 

[cArNiVaLwOrKeR]

Call Magic auto sound in norwalk ca. ask for lee, they have done 1 for me on a 98 12v i think it must be the same...

worked great, start and shutdown... use yellowpages.com to find the #...

 

[Bouncy]

I have the viper with remote start system.



I don't know the model number off the top of my head but I think it was a model 560. It is the alarm and autostarter combined.



Here is the deal with what is powered. That much I know about.



Given the CAN bus on these trucks, the alarm can't just turn on certain features. The alarm has triggers for relays and the relays are wired along side of the stock system.



Thus as the alarm/autostarter is activated... It triggers a relay that powers the systems such as the A/C, lights, starter... etc.



So it is all how it was wired.



I paid almost $600 to have the alarm and autostarter installed. The digital timer was causeing a problem and had to be replaced with an analog timer.



I have my Air Conditioning, defrost, locks, lights, dome lights, glow plug heater, and starter POWERED by the external relays.



It was a TON to rewiring to get it installed.



I basically told the shop... I want an autostarter and alarm installed but I want it to ACT EXACTLY like the stock truck except for the chirp for arming and disarming.



It works great. Only problem was with the digital timer. If you pressed the autostarter button and then 5 seconds later hit the unlock button... It would start immediately instead of waiting the 20 seconds.



It was a problem with the triggering. When the analog timer was installed... It fixed the problem because the timer was wired to interupt the signal. Thus the alarm/starter could NOT start until the timer was done.



Hope this book helps.

 

[Don-T]

Bouncy,

Do you know how the installer was able to get the A/C compressor to come on and cycle on and off as needed? I can use a relay to power the compressor but it won't be able to cycle on and off. I don't think I want to do that. It appears that everything that needs to cycle the compressor is wired to the computer and the computer has an output to run the compressor.



Do you know if the installer used the tach input to determine when the engine starts or did they just use the crank timer and then assume the engine started? My installer wired the tach input to the #1 injector and the alarm has "learned" the signal but it will not stop the starter when the engine starts. Insted they programmed the alarm to just crank the engine for 0. 6 seconds and assume the engine started.



I too have the analog timer for the start delay. There is no way to get to the "Wait to Start" circuit. I thought about using the grid heater signal but I don't think that will be reliable.



Thanks for your input.

 

[Bouncy]

Sorry Don. I don't know how it is actually wired. I just know all the theory behind it.



I had discussed the autostarter with 7 different shops. 6 of them wouldn't touch it because it was a diesel. The one I went with did a lot of research to find out the timer was the ONLY option.



It seemed to me that the trigger could have been taken off the power to the heater grid. As the heater grid was shut off, it would trigger the starter. But then it comes into question that the heater grid also turns on and off several times during the first 10-15 minutes of the motor running.



I have heard that there are 2 different heating units. Thus it seemed that hooking to the power lead of the 1st one would work.



In the end... I stopped fighting the system and just went with the timer.



I don't know why the Big 2 haven't put in harnesses like the electric trailer brakes that allow vendors to have a wiring schematic as to hooking in COMMON add-ons like e-brakes and autostarters.



If they can design enough junk in the CAN bus to keep people out... Seems they would make a little effort to help the customer by allowing EASE of install for componets like these.

 

[Don-T]

I think I am wasting my time trying to get this to work the way I think it should. Maybe DEI will one day come out with an alarm that can talk to the CAN bus system to make it all work. If I were a better programmer I might give it a shot. If I could get the tach signal to work properly I would be happy.

 

[Carlsummers]

Don-T, sorry, I can't tell you how it works, but my 791 does what you want your's to do. I have a 15/30 second delay module on mine because of the heater grid (set to delay start for 15 sec. ). When mine starts, the fan, AC everything except the radio is working. When the key is inserted and placed in the "on" position, and the brake pedal is touched, then everything acts as though the truck was started manually. I'll try to get with my installer and see what he says, if you haven't fixed this yet.....

 

[Don-T]

Any help would be great. I can live without the A/C compressor not coming on (but it would be nice). I don't like the way the remote start works. I don't undestand why the tach signal (which the alarm has learned) won't stop the starter when the engine starts. DEI refuses to let me talk to a tech about it. For that reason I am tempted to rip it all out and not do business with them any more. The problem with that is I don't know who else makes a good alarm / remote start / cool down system and if it would work any better.

 

[ropinfool2]

I don't have an alarm or remote start system on my truck, and my a/c compressor does not work until the water temperature comes up to a certain temp. Here in So. Ca. it can get hot, I want the thing to work right away!! John

 

[Don-T]

ropinfool2,

I don't understand that. If I start it with the key the compressor clutch engages within a few seconds weather the truck is cold or warm.