06 ford f250, viper 7901

I've spent that past several days combing through pages and pages of earlier posts looking for specific information and have had some luck and some questions answered.  Here is what remains:

1)  In reading all the threads, it sounds like hooking up the Accessory Output (Orange H3/3 wire) seems to be necessary to ensure that the heater or A/C starts warming or cooling the interior immediately following remote engine start (depending on how I left the heater & A/C when I last shut down the vehicle).  This doesn't make sense to me.  Once the vehicle is up and running, aren't all the accessories (radio, heater/AC) functioning as they were last left when shutting down the car?  If I did not hook up the Accessory Output wire, are you saying that the vehicle would start and run, but all the other items that normally are powered when the key is turned to the ACCY position would NOT function?  Simply need to understand.

2) On the primary harness (H1), there are two wires that confuse me: H1/4 (WHITE/ brown) which is the Light Flash Isolation Wire - Pin 87a.  How is this wire used and where would I attach it on my 06 F250?  The other wire is the H1/11 (White) which is a Parking Light Output wire.  Don't understand which of the two would be hooked to the parking lights.  Will a relay be required, or will the system allow the vehicle's onboard relay to be used?  The existing Code Alarm (with Ford factory part number, etc.) is wired directly into parking light wire & without a relay.  Could it be that the Code Alarm can handle all the amps? (I'm removing the Code alarm unit).

3)  After reading the install manual, I am a bit fuzzy on how to hook up the Remote Start/Turbo Timer (H1/H10) wire.  The manual states that a negative pulse will be necessary on this wire for the remote start to activate and deactivate.  Well, the Factory Alarm Disarm Output (H2/1) wire sends a negative pulse anytime the remote start is activated or doors are unlocked with the remote.  Should I simply connect the H2/1 wire to the H1/H10 wire which needs that negative pulse to have the remote start activate and deactivate?

4)  And finally, how does this 2nd Unlock Output (H2/6) wire do its thing and what should I hook it up to.  Presently the vehicle has a dealer-installed Code alarm installed which does unlock the drivers door on first unlock command and then the remaining doors when "unlock" is pressed the second time.  Is it the alarm or vehicle onboard systems that enable this functionality?  If I do nothing with this wire, but hook up my door lock and unlock wires on the Viper 3-pin harness.  How will my door locks function?

Many thanks for any help you can provide.  If these topics have been addressed already in other posts that I've missed, please feel free to simply paste a link so that you don't have to repeat yourself.  I hate to start a new post that gets repetitive but I'm not finding any more information I need the more I dig.

1) in physically putting the key in the IGN and turning it you are essentially shorting specific points in the switch..... since under remote start the switch never physically turns you have to power every leg of the switch manually...... think of a remote starter as a phantom ignition switch..... if your particular vehicle needs ACC powered to control the HVAC circuit then the remote starter will need to power this circuit.... if the vehicle needs to see 2 different IGN circuits powered then the remote starter has to be connected to each individual/independent IGN wire..... etc. etc....   simply having the car start does not guarantee that other items in the vehicle will turn on if that circuit is not be powered

2) dont worry about the WHITE/ brown wire this is used mainly in Chrysler vehicles that require a muliplexed lighting circuit.... just use the white wire.... and select polarity based on the vehicle itself....

3) dont worry about this... if the vehicle does not have a turbo this circuit isnt relevent.....

4) if the vehicle requires a double pulse or allows for progressive unlock, hook the 2nd unlock wire to the blue first unlock wire in the 3 pin door harness plug on the Viper.... 

Thanks Kevin, you clarified some important stuff.

1) The light bulb has come on and I understand.  I need to take another look at my Ford's wiring diagram and see what needs to be powered on "accessory".  Heater/AC is important, radio not so important, seat heater important, etc. 

2) Ok; will not mess with Light Flash Isolation wire.  Vehicle requires (+) polarity feed to the lighting system.  I simply need to determine if I need to install an external relay to handle the amps.  I think (but am still trying to verify) that there is already a factory relay on the vehicle.  Factory manual seems to indicate there is, but I'd like to verify before I blow something up. Any suggestions?

3) The vehicle does have a turbo; it's a 6.0L Turbo Diesel.  But here is what the Viper manual says about this wire:  "This input comes from the factory set to 1 activation pulse.  This means that it is necessary to have a single ground pulse on the WHITE/ blue wire for the remote start to activate or to deactivate." To me, it sounds like it is required for remote start to function whether you want to use the turbo timer feature or not. Still unclear on that one

4) I can hook up the 2nd Unlock wire as described, but from a systems standpoint, I don't understand why Viper would require a dedicated wire for this.  Would seem sufficient to me to simply push the UNLOCK button twice within a specified period of time.  Doesn't each pushing of the UNLOCK command the same signal to come out of the Viper "brain"?  Sorry, just want to understand the logic of the system in case I run into trouble.

New question: It is my intent to use the dome supervision in lieu of door trigger.  When the door is opened, 12V is applied along this wire.  Can you see any reason why I can't attach the Dome Lt Output (H1/9) to this same wire (with appropriate relay)?  Therefore I can have the dome illuminate when I disarm vehicle or if I wish to program one of the Aux outputs to do the same, etc.  If I do connect both to the dome wire, do you think I would need a diode?  Theoretically both the "disarm" and "dome" signal would be fed at the same time and shouldn't trip the alarm right?  Only an experienced installer like yourself would know.  Help.

Thanks for your time and feedback.

wont need a relay at all for + Pos park lights... just hook up the white wire....

I've done turbo diesles before and dont remember ever hooking up the Turbo Timer wire for any reason...i'm a bit fuzzy even on it's function but if i remember correctly it just allows a slight (1-3 min) run time after shutdown to allow the turbo to spool down..... anyone on here that knows more than me (thats easy) about Turbos can probably answer this better.....

not on all models... some toggle between a lock pulse and an unlock pulse... thats why certain models give you a dedicated 2nd unlock output....

the issue with using dome light as a trigger is if the vehicle has a theatre lighting circuit that stays on after the doors are locked... it will be sensed by the alarm as a door left open and either shut down that zone or trigger a door ajar error on the remote......

You have a valid point with the domelight output.  Some wiring diagrams (including the one from DEI) direct the installer to use the dome supervision in place of door trigger.  That seems to be bad advice to me because my dome light does stay illuminated for 25 seconds after the last door is closed on the vehicle.  I don't feel like waiting for 25 seconds to elapse before arming the alarm.  As such, I am going to have to use the individual door triggers.

I have found the four door trigger wires, but am having a difficult time figuring out the polarity when a door is opened.  The vehicle DOES have a factory remote keyless entry system and the connector is a great spot for taking a DMM reading on all four door ajar wires.  The problem is that I'm not seeing a difference in voltage between door open and door closed.  Frustrating.  Any suggestions?

Really??? I'll dig into the install manual and owners manual to read up on this.  I was hoping there was a way I could program an arming delay (say 30 seconds or so) until after that dome light shut  off.  Sure would be easier to go that route than having to hook up diodes to each of the four door trigger wires and such.

Change of subject...

My F250 has a factory alarm otherwise called a Vehicle Security Module (VSM).  While the Viper unit has the ability to pulse the arm and/or disarm wires on the VSM, the Ford wiring manual does not indicate that it has  an arm or disarm wire.  How should I deal with this?  No other posts seem to address how to wire into the Ford VSM.

Thanks in advance for your help.

Both problems above solved.  Used dome supervision for door trigger and have not wired anything into Ford VSM.  System is installed and working great with one small exception.  I'm fairly certain that I am going to have to energize another "accessory" wire in the ignition harness as I do not believe my glow plugs are heating up.  I believe this because I do not see the "wait to start" indicator on the instrument cluster illuminate when using remote start.  Here is my question:

Rather than purchasing and having to install an additional external relay, can I not use the Flex Relay feature on this unit?  It can be programmed as a 2nd Ignition, Accessory or Starter relay (probably why they call it a "flex" relay).  If I am correct, I need to understand how to properly wire the Flex Relay.  Interpretation of the manual causes some confusion on my part.  Am I correct in the following:

RED / White (H3/2) wire is called the Flex Relay input wire (87).  Wire this to 12V constant power.

Pink/White (H3/7) wire is called the Flex Relay output wire (30). Run this wire to the appropriate 2nd accessory wire in my ignition harness so that my glow plugs get power during the Wait to Start timer.

Pink/Black (H3/8) wire is called the 87a of Flex Relay.  Don't need to hook this wire up to anything.

Do I need to run any other wires to get the Flex Relay to do its thing?  Do I need to do anything with the Remote Start Aux Output wires (the Pink/white one in particular) to have the Flex Relay operate properly?

Final question: What is meant by polarity feed?  Does this always imply that the polarity feed wire will be attached to the relay 30 terminal?  I get a little confused when the manual calls the H3/2 wire the "polarity feed" wire for the Flex Relay.  I had always thought that power is fed into the 30 terminal and then the 87 terminal would be the output terminal when the coil is activated.  I know that either way it will work.  Just a nomenclature thing and I want to get it right.

Thanks for the forum help and hope that I can pass on my experience on an otherwise successful install on a 06 Ford F250 diesel.

Dear 12v moderators,

I'm trying to follow the posted rules by first digging through the blogs and looking for answers already posted rather than starting a new thread at the drop of a hat.  However, I have yet to get a response when I post a new question on an existing thread.  Should I just go ahead and start a new thread?  It seems to be the only way I can get a little help.  Just want to do the right thing.