06 f150 w/5704 remote start sets of alarm

Installed a Viper 5704 in my 06 F-150 with the help I gathered from other's posts. I had a couple issues I couldn't find any info on and am hoping for a little help with these. 1.) With alarm armed, remote start sets off the alarm and kills the remote start. Alarm zone info says door open. As suggested by others, I diode isolated the 4 door triggers at BCM during install. If alarm is disarmed, remote start runs without issue and I can re-arm once it's running. 2.) Tapped an ignition coil wire for tach, but system won't learn it. I swapped settings over to Virtual tach and it's running fine. I have read that fuel injection wires are better tach signal; any reason I should bother tapping it or should I keep running in virtual mode? 3.) I didn't wire domelight supervision because I was hoping the factory keyless supervision would take over. It doesn't. Am I correct in saying that because the truck wire is (+) (BLACK/ lt. blue) and the viper is (-), all I need to do is wire up a relay to convert to (+) and tap the BLACK/ lt. blue to get the factory supervision back? 4.) And finally is it possible to wire the remote start so that when it times out the radio doesn't stay on? Thanks so much for your help.

With the viper 5xxx platform remote starters, virtual tach has worked best for me in those trucks.  I have used injector and coil pack wires.  Sometimes they program and sometimes they do not.  If they do, as soon as it gets cold out the truck won't start.  I don't even waste time running a tach wire in new f150s.  as faR as your domelight, you are correct in that all you need to do is invert the signal with a relayAdvanced

dasbogie wrote: With the viper 5xxx platform remote starters, virtual tach has worked best for me in those trucks.  I have used injector and coil pack wires.  Sometimes they program and sometimes they do not.  If they do, as soon as it gets cold out the truck won't start.  I don't even waste time running a tach wire in new f150s.  as faR as your domelight, you are correct in that all you need to do is invert the signal with a relay

Thanks so much dasbogie. I figured if it is running fine without the tach wire then I shouldn't worry about it. That takes care of 2 issues and I don't care all that much about the 4th. Now all we have is: 1.) With alarm armed, remote start sets off the alarm and kills the remote start. Alarm zone info says door open, so somehow the remote start is throwing a door trigger signal. As suggested by others, I diode isolated the 4 door triggers at BCM during install. If alarm is disarmed, remote start runs without issue and I can re-arm once it's running.

Which alarm is being set off? Is the factory horn going off or the aftermarket siren? Where did you connect the factory arm/disarm outputs to on the vehicle? Do you have ANY other connections on the door trigger inputs (both + and - inputs) besides the 4 isolated door triggers? As for the radio, there are a couple options: 1) Remote start and shut down with the remote (while sitting in the vehicle) and watch the radio. I have yet to see a single vehicle that does not time out the delayed accessory circuit after a few minutes. This may be 5 min or it might be 20 min... each vehicle is different. If it does time out, and you don't mind it staying on for that amount of time on the rare occassions that you shut down by remote or the r/s times out (you'd be surprised at how rare that actually happens) then just leave it and be happy with one less connection to make. 2) Diode isolate the factory re-arm wire between the factory re-arm and the driver door pin... however, with this method you may find that you will need to temporarily interrupt the door trigger circuit with a relay so that it does not set the alarm off when it sends the signal to turn off the radio.Kenny

Owner / Technician

KKD Garage LLC

Albany, NY 12205

offroadzj wrote: Which alarm is being set off? Is the factory horn going off or the aftermarket siren? Where did you connect the factory arm/disarm outputs to on the vehicle? Do you have ANY other connections on the door trigger inputs (both + and - inputs) besides the 4 isolated door triggers?

Thanks for the reply. It is the aftermarket (viper) siren that is going off. I didn't connect the factory arm/disarm wire as I only had factory keyless. I have no other connections on the door triggers besides the 4 isolated connections on the (-, green) side and I cut the viper's (+, violet) trigger wire within a few inches of the brain.

offroadzj wrote: As for the radio, there are a couple options: 1) Remote start and shut down with the remote (while sitting in the vehicle) and watch the radio. I have yet to see a single vehicle that does not time out the delayed accessory circuit after a few minutes. This may be 5 min or it might be 20 min... each vehicle is different. If it does time out, and you don't mind it staying on for that amount of time on the rare occassions that you shut down by remote or the r/s times out (you'd be surprised at how rare that actually happens) then just leave it and be happy with one less connection to make. 2) Diode isolate the factory re-arm wire between the factory re-arm and the driver door pin... however, with this method you may find that you will need to temporarily interrupt the door trigger circuit with a relay so that it does not set the alarm off when it sends the signal to turn off the radio.

Good idea. I will see how long it takes to time out before I try doing anything else.

As a process of elimination, I would temporarily disconnect the door trigger input to see if it is something internal to the brain or a backfeed from one of the door pin wires. If the problem goes away, retest all of your door pin wires after the diode to make sure you have the correct wire and that the diode is facing the right way. Also test each one while remote starting (with the door shut) to see if you are getting a backfeed somewhere in the car.Kenny

Owner / Technician

KKD Garage LLC

Albany, NY 12205

offroadzj wrote: As a process of elimination, I would temporarily disconnect the door trigger input to see if it is something internal to the brain or a backfeed from one of the door pin wires. If the problem goes away, retest all of your door pin wires after the diode to make sure you have the correct wire and that the diode is facing the right way. Also test each one while remote starting (with the door shut) to see if you are getting a backfeed somewhere in the car.

I will test as you suggested this weekend and get back with you. Thanks again.

offroadzj wrote: As a process of elimination, I would temporarily disconnect the door trigger input to see if it is something internal to the brain or a backfeed from one of the door pin wires. If the problem goes away, retest all of your door pin wires after the diode to make sure you have the correct wire and that the diode is facing the right way. Also test each one while remote starting (with the door shut) to see if you are getting a backfeed somewhere in the car.

Finally got some nice weather and a few minutes to test things out. First, I disconnected the Viper's (-) trigger input wire and the truck remote starts without issue. My assumption is that the brain is OK and door trigger wires are clearly the issue. I then tested each wire after the diode as suggested and all four throw -.34V when the respective doors are open. I remote start and at the same time test the post-diodes connection (all four tied together, not individually) that was previously connected to the Viper input and see nothing. I reconnected the Viper input, remote start, and within seconds it sets off the alarm and shuts down (2-way remote says "door open"). Lastly, just to clarify as this is my first experience with diodes, I tapped each of the four truck trigger wires (-) with the striped side of each diode. I then tied all four of the non-stripped sides of the diodes together and connected that to the (-) trigger input of the Viper. I really appreciate your help.

What setting do you have your DMM on while testing? The door triggers should show ground when the door is opened (unless it is a normally open circuit which I don't think it is) Connect the red lead of your DMM to a known 12v source and use the black lead on the door trigger wires. With each door open, the meter should read 12v. Then 0v with the doors closed. Repeat the 2 tests using this method and see what you get.Kenny

Owner / Technician

KKD Garage LLC

Albany, NY 12205

offroadzj wrote: What setting do you have your DMM on while testing? The door triggers should show ground when the door is opened (unless it is a normally open circuit which I don't think it is) Connect the red lead of your DMM to a known 12v source and use the black lead on the door trigger wires. With each door open, the meter should read 12v. Then 0v with the doors closed. Repeat the 2 tests using this method and see what you get.

I am at work, but just ran out to the truck to test as you suggested. I am obviously missing something here. I was initially testing with leads reversed (i.e. black to ground and red to trigger wire.) Now that you explain how to test, it makes complete sense the only problem is here were the results: DMM set to 20V mode and red lead to 12v constant at amp power distribution block. -Door open= DMM reads 12.6v (showing full ground at wire as it should) -Door closed after being open= DMM temporarily reads 9v and then goes back up to 12.3v after 10 or 15 seconds. (I believe this means a temp. +3v at wire, then back to +0.3v. If you open the door again, it goes up to 12.6v. -Remote start= Initially DMM reads 12.3V as noted for door closed above. After start a drop to 9v is seen (just as with above) and stays there while running. As an extra test, I put the DMM in continuity mode (reads "1" with open circuit). Black lead to ground and red to wire gives slight noise at all doors (reads 0.113) and a full beep (reads 0) at the open door (all tested on Ford side of diode). Each individual door worked the same. Is it possible that there is only a 0.3v differential between open and closed doors?