1999 dodge caravan, carvox unlock

Hello,
I have a 1999 Dodge Grand Caravan

I installed a Carvox King Eagle alarm system in it last year.
I only connected the positive and negative power wires and the power door lock and unlock wires because all I really want to do is have a pager that I can use to lock and unlock the doors for right now.

The alarm has always locked and armed as expected.

The problem is DIS-Arming and unlocking.

This vehicle has two large white electrical plugs located at the bottom of the electrical junction box near the drivers feet which plug into the BCM.

The interesting part is that if I UNPLUG the large white BCM plug closest to the center of the vehicle, the lock and unlock functions work perfectly...however the factory alarm is then unavailable along with several other critical vehicle functions.

Apparently, some connection associated with the BCM plug 1 (according to the FSM) is defeating the unlock / disarm.

Does this sound like anything familiar or am I in for a very painful wire by wire / system by system analysis? (If I could even do it).

Thanks for any replies.

I should add that I have a 4000 ohm resistor on the end of the alarm Lock wire and the other end of that resistor is soldered to the WHITE/ dark green vehicle wire.

I have a 680 ohm resistor similarly connected to the end of the alarms Unlock wire and it is soldered to the same spot as the Lock wire (on the WHITE/ dark green vehicle wire)

As noted in the first post, lock AND Unlock both will work as expected IF....I unplug the large white BCM plug number 1 (closest to center of vehicle)

thx

Good morning, I had a similar experience with a 96 chrysler sebring. Do note I'm not certain all the wire colors are the same, but you can try this; Instead of hooking alarm wires, with resistors, to the left door mux connection (wht/lt grn. Hook it to the vtss sense wire (lt grn/org)in the same connector. This connection allowed the new remote/alarm to activate all the oem functions of the body control module in my sebring.

good luck

I am not familiar with the CarVox line and cannot find any install guides but...    

If your alarm brain does not have built in relays  for the Lock and UnLock outputs try this.  Take a 665 ohm resister with wires soldered to both sides, attach one side to a solid ground.  Lock and arm the car.  After the alarm sets, try an unlock by touching the free side of the resister wire to the cars' WHITE/ Dark Green lock wire.  The "Official" resistor values listed are 4020 and 665 ohms.  I'm not sure if the slight resistance difference matters much but some alarm brains recommend relays for installs like this.

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Soldering is fun!

Thank you both for your replies.

I will try both your suggestions.

This situation is VERY ODD BECAUSE if I simply unplug BCM Plug 1 (closest to center) the lock & unlock works fine

If the resistance is critical, Radio Shack sells 330 ohm resistors in a 5 pack.  Measure them all and pick the highest two.  Put those two in series and you should be very close to 665 ohms.

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Soldering is fun!

My alarm does have built in relays and the LOCK function works fine.

Also, the UNLOCK will work just fine ( if I unplug the BCM plug that is not related to the door locks ).   There are 2 BCM plugs for this vehicle.

For some reason, when the other BCM plug is IN, the UNLOCK stops working. I know what all the other wires are and i could unplug them one by one until I isolate the circuit that is causing the problem, but its very difficult and time consuming to unplug every wire from the BCM and it requires a special tool.

I will offer a $20.00 PayPal payment to whomever offers me the exact solution that fixes this problem. I know it's not a whole lot, but I'm out of work presently.

Thanks

On the 1999 there is an easier solution. Notice there are 3 relays that are on the front of the fuse box that click when you lock/unlock? One is lock, one is unlock drivers door and one is unlock all doors. They are triggered by a simple ground pulse. Simply remove the relay and attach your lock wire to the relay post that triggers the relay and pop the relay back in. No resistors needed and you can get 2 stage unlock because of the 2 unlock relays. I can't remember whether it is pin 85 or 86 that triggers but a test with a DVM will tell you.

This solution will not arm or disarm tho...

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Mike M2
Tech Manager
CS Dealer Services

Thanks Mike

So close....but I Do need the factory alarm to arm and disarm along with the lock and unlock.

Do you have the proper WHITE/ dark green wire? I recently did a 98 caravan and the plug @ the BCM had 3 of them I believe. If there wasn't 3 of them there was definitely 2. I put a stripped wire into the molex plug where the factory wire enters the plug, then plugged it back into the BCM. I operated the locks from the drivers door and put a meter on the other end of that wire I stuffed into the molex plug. I watched for negative pluses and I had the right one on the first try. I kinda remember it being more to the center of the plug versus around the edges??? But test anyway. I don't know what the other WHITE/ dark green do...
After I wrote all this, I noticed that you did not mentioned if you are using relays or not. I used relays and the values 4020 and 665. If you are not using relays, I would test to see if its the right wire first, and then if not using relays is the problem. Take one end of the unlock resistors to the WHITE/ green and the other directly to ground and see if it unlocks. If it does use relays. I "think" you can do it with out relays but you need to use a different resistor value as the remote starter lock/unlock outputs have an internal resistance that will interfere with the resistor values. Using relays eliminates this problem. The car i did with relays worked on the first shot with relays.

Hope this helps,
Frank

Ok, I reread you post. I had skipped around the first time and noticed most of my post was either covered or didn't apply(you have onboard relays). Sorry, but I would still double check you have the correct WHITE/ green though.

flobee4 wrote:

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Do you have the proper WHITE/ dark green wire? I recently did a 98 caravan and the plug @ the BCM had 3 of them I believe. If there wasn't 3 of them there was definitely 2. I put a stripped wire into the molex plug where the factory wire enters the plug, then plugged it back into the BCM. I operated the locks from the drivers door and put a meter on the other end of that wire I stuffed into the molex plug. I watched for negative pluses and I had the right one on the first try. I kinda remember it being more to the center of the plug versus around the edges??? But test anyway. I don't know what the other WHITE/ dark green do...
After I wrote all this, I noticed that you did not mentioned if you are using relays or not. I used relays and the values 4020 and 665. If you are not using relays, I would test to see if its the right wire first, and then if not using relays is the problem. Take one end of the unlock resistors to the WHITE/ green and the other directly to ground and see if it unlocks. If it does use relays. I "think" you can do it with out relays but you need to use a different resistor value as the remote starter lock/unlock outputs have an internal resistance that will interfere with the resistor values. Using relays eliminates this problem. The car i did with relays worked on the first shot with relays.

Hope this helps,
Frank

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Thanks Frank,
Your hint about not using external relays changing the required resistor value is something I will explore. I did try going down in resistance from 665 down to 550 but it did not seem to make any difference. What I haven't done is gone the other way and tried a higher resistance. I may try this over the weekend.

What baffles me is that it works PERFECTLY if I simply unplug the other BCM plug.

Is it working from the drivers door key cylinder? If you don't use the factory FOB to arm it and just close all the doors and lock the doors using the drivers door cylinder, the "alarm set" light should come on steady and start blinking after about a minute. Verify that it working that way.

I can definitely lock and unlock the van with the key.   That does work fine.   However, I was really wanting a remote to lock and unlock the doors and at the same time arm and disarm the factory alarm along with the carvox.   I do not have a factory key fob.

The ONLY thing I'm lacking is unlocking with my carvox remote.

I'm going to try a higher value resistor. If that doesn't work, I'm going to reconnect the alarm's "Factory Disarm" wire to the van's Door lock wire which is white with a dark green stripe.

Maybe the alarm has to be "Disarmed" an instant BEFORE the locks will unlock?