dei remote start confirmation output?

howie ll wrote:

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What are you trying to do?  There is a neg factory alarm output after start has commenced

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I'm using my Viper as a push button start setup in my car...there are a pair of relays powering the ACC and IGN, which are switched on using a latch relay setup, triggered by the ACC output of the Viper...

I'm thinking if there is a neg. output AFTER the Viper has successfully started the car, I can use this to switch off the Viper's power to the ACC/IGN, possibly thru grounding the hood-pin.

I thought the factory alarm output was triggered at the start of the Vipers remote start sequence, not after the car has started?

Oh, your thinking of the GREEN / WHITE factory rearm?

Unfortunately this only triggers AFTER the remote start has been shut down...won't work.

How are you latching the relays?  Are you going to still be using a key?

It's not really safe to "self latch" an electromechanical relay because a large bump can cause them to unlatch (after all, it's only a magnet pulling away from a spring at that point - any contact bounce will drop the relay out).

You could possibly set something up with the IGN output from the alarm and the brake input from the car.  If the remote start IGN out is on (which would ONLY be on if the remote start thinks the car is running) and you press the brake have your system take over.  It, theoretically, should be able to switch over before the remote start drops out.  Of course you will need to add a level of security there to prevent someone else from driving off with the car.

KPierson wrote:

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How are you latching the relays?  Are you going to still be using a key?

It's not really safe to "self latch" an electromechanical relay because a large bump can cause them to unlatch (after all, it's only a magnet pulling away from a spring at that point - any contact bounce will drop the relay out).

You could possibly set something up with the IGN output from the alarm and the brake input from the car.  If the remote start IGN out is on (which would ONLY be on if the remote start thinks the car is running) and you press the brake have your system take over.  It, theoretically, should be able to switch over before the remote start drops out.  Of course you will need to add a level of security there to prevent someone else from driving off with the car.

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I'm using a pair of micro relays as a momentary/latch setup (as described in the 'relay' section of the forum), which drive a pair of Bosch 30A relays, 1 for the IGN the other for ACC...these relays probably don't have the weight/inertia to have it unlatch from a bump...

I'm using a timer mechanisim for powering up the car without starting it...hold 'start'  for 5 seconds...as the DEI autostart is looking for 2 ground pulses, it ignores the button 'hold'...

You can see in the schematic, how the pink/white ACC relay output also triggers the timer, and it's designed to switch off the autostart after the lapse time (5 sec), but in testing, this doesn't work...I can see the timer is active (LED) when the autostart fires, but the relay output on the timer never fires...

It could be because of the V drop when the starter motor cranks, as I can see the LED on the timer dim considerably...this was the best solution I could come up with for shutting down the DEI after starting.

(BTW, I'm not totally sure of the diode directions in the schematic...I know I have it setup properly on the actual wiring)

What are you doing for security?

It's not the size of the relay that matters, it's the fact that the only thing that keeps the relay latched is a magnetic field that is pulling against a spring loaded lever.  If the relay is inside the car it will abosrb shock when you hit potholes and other bumps in the road. 

It's actually common for digitally controlled relays (ie not self latching) to have contact bounce when hitting bumps, but the bounce is so short you can't detect it in the car.  If the relays were self latched as soon as the lever came away from the contact power would drop from the coil and the latch would drop out.  A much better route would be to use either a solid state relay (no moving parts) or completely digital circuity.  It would be MUCH safer in a moving vehicle.

For security, you still need to use the transponder key...and I'm thinking about adding a disabling relay on the button itself...and of course, the DEI Viper alarm. The relay will be a bit of work, because the button is a ground signal, not a positive signal, like the OE starter.

I removed the original key tumbler, and replaced it with a modified (it doesn't engage the IGN switch inside) tumbler from a different (but same model) car...this way my key fits into the cylinder, but doesn't turn :) The key needs to be in place to start, but once started, it can be removed or left in place. Basically, it's a key holder for the transponder/chip key.

The IGN switch guts are already switch over to RUN, and the original harness is unplugged and hidden up out of the way. This way, the steering wheel is unlock without having to completely modify the key/cylinder/switch mechanisim in the car.

In the event of massive failure of my push button start, I'll be able to plug the harness back in (with some work!) and use the DEI to start the car still...

KPierson wrote:

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So then the actual remote start won't work because there is no bypass installed for it?  Isn't there like a 5 second delay between the ignition turning on and the starter output turning on?  That's going to be a long delay every time you get in the car!

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I don't understand what you mean by bypass?

The DEI is hooked up to the car  independantly from my starter rigging...the only delay is the DEI itself. As soon as the Viper powers up the ACC/IGN, it powers up my latch (and seperate ACC/IGN circuit as well). The 5 second delay is designed to disengage the Viper, and for powering up the car without starting it, not to delay the remote starting....

Except the timer isn't functioning properly after the starter turns, likely due to the V drop...so the DEI brake pedal kill is still used as a backup...

You said that the transponder key is required for the pushbutton start system to function - so does that mean the remote start system won't function without the key present?

The delay I was talking about is with the remote start sequence itself - DEI remote start systems turn the ignition on, then wait a few seconds, then start the car - there is definately a delay in the start up of their systems. 

KPierson wrote:

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You said that the transponder key is required for the pushbutton start system to function - so does that mean the remote start system won't function without the key present?

The delay I was talking about is with the remote start sequence itself - DEI remote start systems turn the ignition on, then wait a few seconds, then start the car - there is definately a delay in the start up of their systems. 

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Correct...I don't use the remote starter in a typical sense, however, I do have the bypass module (not installed)...I think in my setup, using that would seriously compromise the cars security...

Yeah, there is a few seconds for the DEI to start...gives me time to buckle up! :)