I saw that someone posted a message about alarms here and a few people said that they were installers. I have an old Viper 300 alarm on my NX. It was installed in June of '98. Recently, it has stopped responding to the transmitter and I have had to disarm it using the valet switch. Today, I disconnected the battery for an intake install and I thought that might reset and fix the alarm. It had the opposite effect. The alarm is going bonkers. I got it to disarm with the valet switch, but I still couldn't get the car started. It is like the alarm is sucking power fromn the car. I don't know how to explain it. When I try to start the car, everything goes dead. It powers up slowly, as well. The dash lits are dim and then eventually (within 5 seconds), they get bright and I can use all of the accessories.

I would like to get the alarm working again, but I really need to get the car started, so I'll disconnect the alarm if need be. I have no idea how the alarm is connected or what the proper way to disconnect it would be. I would like to get this sorted out tonight so I can start the car and go to work tomorrow. Any help would be appreciated.

Thanks,
Ben
'93 NX

Normally all the wires your alarm is connected to are just splices, you can just yank the harness out of the brain of the alarm and drive. However, it sounds like you have a starter and maybe ignition kill relay on your alarm. This may require some re-wiring to get it going again. If you get into it and need help drop me a line - I use to install and still do side work. I'm pretty familiar with my NX's wiring as I did a remote start/alarm recently.

Chris

Thanks for the reply. Part of the problem is that I didn't install the alarm, so I don't know where the brain is. I do know where the siren and radar sensor are. Can I just follow the wiring from there?

Also, the alarm does have a starter kill. Any idea of how that might be wired in?

Thanks,
Ben
'93 NX

Normally its just a relay in between the actual starter wires, drop the lower trim piece in your car under the drivers dash and then drop the lower plastic part of the steering colum, you should finde about 6 heavy gauge wires running under the dash together, thats all your ignition wires, you'll find the starter wire cut in half, I think its black/white or black/yellow - I cand double check if need be.

Chris

If the starter interrupt relay was wired-in the way DEI recommends, then by simply cutting power to the alarm brain itself you are already disabling the starter interrupt. All you have to do is drop your lower dash and trace the wires going to the brain. There should be a red wire with a fuse located about 3in. away from the brain. I believe it is a red (10 amp) fuse.

The relay for the starter interrupt could have gone bad, but that is unlikely. If the starter is clicking but not turning over, then you have a bad starter. Another thing is that you mentioned the car is slow in starting. If the voltage drops too low, the alarm freaks out and doesn't know what to do. You might want to check your alternator/battery at this point.

Actually - thats opposite the way DEI recommends FYI - their alarms are all Fail-Safe (or at least have been for the past 4 years at least). They are wired to the relay's normally closed pin, so that in the even that the alarm dies or the coil goes up in smoke you can still start your car. The only time the relay breaks the connection to the starter is when you arm it, and a (-) signal is sent from the orange (-) when armed output wire on the alarm brain. Honestly, its the best way to run it IMO, if someone really wants to steal your car they will, and theres a slim chance that will ever happen, however the alarm/relay/or a fuse causing the alarm to not work failing is a lot higher. I'd be pretty pissed if I couldn't drive my car because of that lol....

Chris
Spent more time laying down in cars than in bed for several years.

hmmmm... It does seem as if maybe it isn't getting enough power. The thing is that all of the other accessories work fine. It does look like there is some corrosion on the battery terminals, so I'll sand them down and see if that helps. I'll measure the voltage across the terminals and see what I get.

I know it isn't the starter because I just rebuilt it and the car has been starting like a champ.

Thanks for all of the suggestions! I'll keep you posted on what I find out.

Ben

The problem was the power. I checked the voltage with the ignition off, and it was fine, but with the ignition on, there was a drop across the power cables. I cleaned up the positive terminal and the car started up. This is with the alarm detached. The alarm still will not respond to the transmitter.

When I pulled the panel off of the car, the valet switch pretty much fell apart. I am going to radio shack to replace it tomorrow. If the valet switch is not hooked up, could that cause the alarm to not respond to the transmitter?

I took the actual alarm apart, and when I did that, a light green circular rubber thing fell out. It looks like it has a magnet in it. It also has 2 "handle" things on either side. They are like half loops. What is this? It appeared to just be loose inside the alarm case.

I would appreciate any ideas on how to fix the alarm. I mainly want it for the keyless entry.

Thanks for all of the help!
Ben

Actually - thats opposite the way DEI recommends FYI - their alarms are all Fail-Safe (or at least have been for the past 4 years at least). They are wired to the relay's normally closed pin, so that in the even that the alarm dies or the coil goes up in smoke you can still start your car.
By:MauiBlueGride

Exactly-so by cutting the power to the alarm, you have disabled the starter interrupt-as I mentioned in my above post. =-) Without power going to the brain, there is no Negative Armed Output from the orange wire going to the relay.

As for the green thingie with handles on the sides, I'm not sure as to what that can be. Hopefully it isn't conductive and didn't short the breadboard while it was floating around in there. The 2 half loops are in there for programming purposes. I can't remember thier functions off the top of my head since they have since gotten rid of those.

Sorry bob - I thought when you meant disable you meant disable the starter circuit, not the starter kill feature lol....


The green thingy - perhaps this is/was a shock sensor????
The alarm should function without the valet switch, honestly, with no model#'s, manuals, or ideas on how this thing was hooked up - I'd yank it.

Chris

I used to have the Viper 300 in my truck. That green thing that fell out could have been one of the four loops that they cut to able/disable certain features in the alarm but I think you'd recognize it as being a short piece of wire. Is there any printing on the green thing? It could be a capacitor that broke off of the circuit board if it does. My brother in law has my old 300 installed in his Camaro and has the paperwork at his place. I can get it for you if you want or you can probably get it from DEI as well, maybe from their website.