Recommendation for a simple remote door unlock?

I have a 2017 Dodge Grand Caravan GT which comes with a FOBIK with remote lock/unlock, door open/close, start, etc. One problem is that the FOBIK is overly large. Another problem is that the existing system will not let you leave the car running with AC on, but lock the doors if I want to make a quick stop at the store or something. I am in Florida and frequently have my dog in the car with me. Using the existing system means I have to stop the engine and remove the key, lock the doors and then use the remote start to start the car again. Way too much trouble - not too mention wear on the starter. So I am looking for an aftermarket door lock/unlock system with a smallish remote that I can add to the existing. All I want the remote to do is lock/unlock the doors. It does not need to be two-way or have any ridiculous range - twenty feet is fine. Do any of you have recommendations? Thanks!

Interesting question and need. If I understand correctly, your sole use for this add-on is to lock and unlock the minivan while it is left running for short periods with the key in the ignition?     The main reason I've set specific limits on the intended use has to do with the fact that your minivan probably has the Factory Alarm system. The add-on RKE system would only control the door locks and not the Factory Alarm system. Shouldn't be an issue if you only use the factory FOBIK to unlock the armed minivan and you must carry and use the FOBIK to start the engine anyway due to the transponder chip. While you didn't mention it, I'm assuming that cost is a factor. To be able to control the Factory Alarm system a full featured bypass module ( $60 ) is needed while just controlling the power locks could be done with a cheap Asian RKE system for ~$12. The next issue is remote size. Seems that most of the high quality RKE systems have 3 or 4 button remotes and are not all that small. You would have to check to see if any given remote would be an acceptable size. Last point is obtaining a unit with built-in lock relays. Your minivan needs (-) signals through a 100 and 330 ohm resistors to actuate the power locks. Built in relays will ensure reliable lock control. With all that in mind, take a look at the Avital 2101L. It is good quality, has decent range ( easy 300' ), built-in relays and costs ~$50. However, the remotes are 4 button and might not be as small as you wanted.   On the other end of the spectrum, here is a link to a very inexpensive unit that has a much shorter range and possibly smaller remotes. Can't speak to the quality of the unit but installed properly could be acceptable. http://www./itm/Universal-Car-Remote-Central-Kit-Door-Lock-Vehicle-Keyless-Entry-System-OY/272206173679?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649 We can help with the actual wiring of the chosen unit to the minivan once you decide.Soldering is fun!

Kreg357: Thanks very much for the reply and the recommendations. Part of my motivation is that my last vehicle was a Ford with the keypad on the door. That worked perfectly fine for all of my needs. I could leave the engine running (for the dog), lock the doors and then use the code to unlock the doors when I returned. Another example is attending football games here at Raymond James stadium. There are several reasons why I never, ever carry keys into the stadium. With the Ford, I could leave the keys under the floor mat and just use the keypad to unlock the doors after the game. That worked very well for a lot of years. I'm not opposed to spending $100 or so for an alternative. The remotes on the Avital 2101L are compact enough. While I prefer to carry nothing into the stadium, those are at least small enough that I could put them on my ticket lanyard or something. And unlike the FOBIK, if an Avital remote got lost or destroyed, it wouldn't involve a trip to the dealer and $300. I am pretty well versed in electronics. From your reply, I am guessing the vehicle has something like a DOOR_LOCK line which normally floats - probably at either 5V or 12V. When that line is connected to ground through a 100 Ohm resistor, one action (either LOCK or UNLOCK) occurs. And when that line is connected to ground through a 330 ohm resistor, the opposite action occurs. Do I have that right? Which resistor does which action? And where is that line available? I am not so well versed with vehicle security and I'm not clear on what the bypass module does. I am guessing that it allows the vehicle to start even though the transponder chip in the FOBIK isn't near the reader built into the switch. Is that close? Would adding a bypass module to the Avital 2101L allow for one of the buttons to remote start the vehicle? Does the bypass module have to be included into the vehicle system by the dealer? Thanks very much for all of your help! Ken Morley I am not very well versed

I guess the big question is if your van has the factory alarm system. A simple test would be to roll down the drivers window, turn off and exit the van, close all the doors and lock it with FOBIK twice. Wait a minute or so and the then reach in the drivers window and open the door with the inside handle. If the horn starts beeping you have the factory alarm system. This is not a show stopper, it would merely limit the aftermarket system to being used to open the van only when the factory alarm was not armed.    You are correct with your understanding of the way the power door locks operate and how the aftermarket system will integrate into the vans power door locks.   Once you locate and verify the Lock/Unlock wire, you can test it by applying ground through the appropriate resistor via a jumper wire. Here is the info on the Lock/Unlock wire : VIOLET/DK GREEN (Lock = (-) 330 OHMS ; Unlock = (-) 100 OHMS ) HARNESS FROM DOOR IN DRIVER SIDE KICK The wire listed is for base models ONLY. On all others, use Light Green/White at the Passenger Door Module, Black 10 pin connector, pin 4, in Passenger door. I have never done this minivan this way. I always go with a full featured bypass module and a Remote Start with Keyless Entry system. You could use a Avital 4103LX system which has similar remotes to the 2101L system mentioned previously. The full featured bypass module would control the minivans alarm system and sliding doors plus bypass the ignition immobilizer transponder system during a remote start. Here is a link to a Pictorial on that gen minivan : https://www.the12volt.com/installbay/forum_posts.asp?tid=134484 While more expensive, going with a R/S w/RKE system and bypass module will allow you to idle the vehicle with no key left inside and control the Factory Alarm system with the aftermarket remotes. Soldering is fun!

Kreg357: Thanks again for being so generous with your time and knowledge - I genuinely appreciate it. I'll do the security test and get back to you. It sounds like using something like the Avital 4103LX with a bypass module might be the better approach. If I use that, do I even need the FOBIK at all? I'm not sure how the bypass module integrates with vehicle security. After installation, does the bypass module have to be "authorized" or something by the dealer? I'm confused about how the vehicle learns to trust the bypass module. Currently, I can remote start the car using the FOBIK only if the vehicle is locked. Air conditioning, lights and audio system all run, but no other accessories are available until I put the FOBIK into the switch and rotate to the run positon. And the time limit is 15 minutes. If I don't insert and rotate the FOBIK within 15 minutes of remote start, the car shuts off. Thanks again! Ken Morley

Going with the 2101L system would be quick and easy if it's only purpose was to lock and unlock the minivan while the Factory Alarm was not armed. The limitations of the factory remote start system would remain. You would still need the FOBIK key to drive the minivan. Just like the factory R/S system, the engine will shutdown if the brake pedal is depressed and the FOBIK is not in the ignition switch and turned to ON or RUN. An aftermarket R/S w/RKE system would allow a longer run time. Depending on the brand, 45 minutes is common. Most aftermarket systems have a "PitStop" mode that allows R/S entry while the engine is running normally under key / FOBIK control. The procedure is : 1. Stop the vehicle and place the transmission in Park. 2. Take your foot off the Brake pedal. 3. Press the aftermarket FOB's R/S button. The Parking lights will flash and come on. 4. Remove the FOBIK / key. The engine continues to run. 5. Exit the vehicle and use the R/S FOB to lock the vehicle. 6. The vehicle will continue to run the engine for the programmed runtime. The full featured bypass module for that vehicle controls most everything through the vehicles CAN Bus system. The bypass module is initially programmed to vehicle during install. It learns the transponder chip code sequence and uses it during a remote start. The bypass modules microcode controls it's functions, accepting commands from the R/S unit and sending those commands to the vehicle through the CAN Bus system.   There is a slight delay difference between an Unlock command from the FOBIK and the R/S fob of 1/4 second due to the extra "distance" the command goes from the fob to the R/S to the bypass module and then to the vehicle. No big deal but noticeable. If you were to go with a R/S w/RKE system, I would not go with a Avital 4103LX if your minivan had the Factory Alarm system ( unless you spent the extra money for the bypass module flash cable ) because you need to program either the R/S system or bypass module to do an Unlock prior to R/S and a Lock after R/S. The Avital 4103LX can't do this. My choice would be a Computar CS800-s or a Prestige APS57E system with an iDatalink ADS AL-CA bypass module. The CS800-s would allow a 45 minute runtime while the APS57E can be programmed to 60 minutes. I believe the ADS AL-CA bypass module comes from the factory flashed with the correct DL CH4 firmware but you could buy the bypass module from a seller that would flash the latest correct firmware for you prior to shipment. While I'm sure you are capable of this install, please understand that there is a lot of research and background knowledge needed to obtain the most suitable aftermarket products, program and configure these items and make the proper vehicle connections.   I would suggest searching for the actual install guides and becoming familiar with them. Knowledge and planning are crucial.Soldering is fun!

Kreg, if the engine was already running, surely using the Avital (I'd also recommend it, it's bullet proof with built in relays) wouldn't affect the factory alarm system since the ignition is already on. Ken, yes you have a very good idea of how that one wire system works, AKA multiplex wiring.