Several weeks ago I installed a battery back-up to my viper 791. the diagram told me to splice the blue wire from the battery to the hood pin switch. everything seemed to work OK (alarm went off with main battery disconnected) but I guess I forgot to check to make sure the hood pin switch functioned properly.

Well, today I noticed that it doesn't. when the alarm is armed and the hood is popped open the alarm doesn't go off. Yet the brain still reads ground as remote start doesn't work if the hood is open.

I'm at work now but won't have time to further diagnose the problem till I get home. I think it is the battery though since that was the only time I tampered with the hood pin switch wire. Any suggestions?

 

Ok i've heard rumors that the blue wire doesn't even have to be connected. It this true information?

 

Will let you know as soon as this stupid seller finally sends mine.

You should try getting those mechanical hood locks that includes (-) output when armed to control starter kill relay.

 

i thought the battery backup worked when the constant wire was cut?

well anyway, you probably wanna try hooking the hood pin wire up to the blue wire from the BRAIN of the alarm.

the blue wire is your instant trigger wire and it should go off

 

well there was nothing wrong except some salt that got in there and didn't create a good contact. I did hook it up correctly.

 

I'm adding a Hood Pin Switch and a DEI 520T to my KARR alarm for my 99 CIVIC 2DR EX. The Brain is hard to identify (no model #), but I can try if you need... I don't think it's relevant...

There is a Green Wire from the Brain's main harness that shows 0v when the Trunk Lid is open, and +12v at all other times (+ lead of MultiMeter on the wire near brain, - lead to chassis ground). It is spliced into a Blue/Black Wire of the Floor Harness, near the driver's side Kick Panel.

I want to confirm that:
1 - This Green Wire is the one I want to splice into, right? Meaning, I'll have: the wire from the Hood Pin; the Neg. Output wire (Blue) from the Backup Battery Module (DEI 520T); and the Blue/Black wire from the Floor Harness... all connected to the Brain's Green Wire, right?
2 - I will need to Diode isolate all 3 wires, with the striped side of each connecting to each of the 3 wires, and the non-striped side "pointed toward" the brain, right?
3 - These should all be connected at a single point, none "in series" (like a pitchfork), right?
4 - Does it matter what kind of Diodes I use? I have some 1N4001 and some 1N4003 Diodes.. any difference in using one, the other, or some combination?

5 - (General) What is the Blue/Black wire in the Floor Harness? I can't figure it out, but I think It's either the Trunk Light, or for the "Trunk Latch"...
[EDIT] - It is for the Trunk Light... http://members.***.net/shaundr....html

Thanks for the help, everyone! I wouldn't even know where to start if it weren't for y'all!
JasonGhostz


Modified by JasonGhostz at 12:40 AM 5/29/2008

 

The blue/black is from the trunk/hatch latch switch, it supplies a ground to the trunk/hatch light and the trunk open warning indicator in the dashthe green of the Karr alarm that is connected to it is the alarms instant trigger for hood and trunk.

You can not connect the 520Ts blue lead to the Karrs green lead unless you isolate the trunk/hatch light from the 520Ts blue output trigger, the blue output trigger is a low current ground, way too low for the trunk/hatch light, the light will draw more ground, [current] then the 520T can supply and at the least will not trigger the alarm, as all the ground is "going" to the bulb to try and light it, at worst it will blow the 520Ts output trigger. 94

 

Thanks, fcm...

So the Blue/Black in the Floor Harness is the ground from the Trunk Latch Switch, which controls the Trunk Light. I was curious as to how it worked, but as long as the Wire behaved the way it should, I guess it really doesn't matter too much.

Regarding the Diode(s):
Do I need to put one on each of the wires leading to the Blue/Black Trunk Latch Wire, the Hood Pin Wire, and the 520t Blue Wire?
Striped side away from Brain?
Connected at one point (none in series)?
Using 1N4001 will be fine?

Thanks again for the help!
JasonGhostz

 

The diode, [no bigger then 3A] needs to be installed on the blue/black between the light bulb and where the 520Ts blue lead is connected, cathode, [white band] end of diode towards light bulb 94

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by fcm &raquo;</TD></TR><TR><TD CLASS="quote">The diode, [no bigger then 3A] needs to be installed on the blue/black between the light bulb and where the 520Ts blue lead is connected, cathode, [white band] end of diode towards light bulb 94</TD></TR></TABLE>
Now I'm a little confused... So, even though I'm connecting a Hood Pin Wire and the 520T to the Brain's Negative Instant Trigger Input (if that's what the Green Wire is), I'll only need one Diode, to be placed on the Blue/Black Wire?

Like this?


I thought I would need to Diode isolate all 3 of them, but...

Thanks again.
JasonGhostz

 

No, that would be correct, as long as the hood does not have a light controlled by the hood pin switch there is no load, and the trunk/hatch open warning light has no power on the other side of it until ign. is turned on, so no load there either.

In fact if a hood pin was added to the alarms green lead and the green lead was connected to the blue/black, whenever hood was open the trunk/hatch light would come on, not so once diode is installed, the trunk/hatch open warning light in cluster will still come on if hood is open. 94