The Lotus Cars Community banner
  • Hi there! Why not register as a user to enjoy all of the benefits of the site? You may register here. When you register, please pick a username that is non-commercial. If you use a name that appears on any search engine commercially, you must pick another name, whether it applies to you or not. Commercial usernames are for supporting vendor use only. If you want to become a supporting vendor and grow your business, please follow this link. Thanks!

Pulled your Cobra alarm and want RKE back for under $25.

11K views 26 replies 13 participants last post by  Drave 
#1 ·
So you have ripped out the evil Cobra alarm system and now you are missing the remote keyless entry. Here is a solution that cost under 25 dollars American, is totally reversible, does not cut into any wires and has better than 100 foot range.

I was installing my shifter system and new cables this spring and in the process I decided to remove the immobilizer and the alarm just as a precaution against bad things to come. After I finally pulled the alarm cable off the module I noticed that the connector looks and awful lot like an ATX connector on a PC power supply. Could it be! Sure enough the connector is a standard ATX connector. Hmmmm…

So I get on line with Amazon and locate this ATX extension cable for less than $6 …OK cool.
https://www.amazon.com/gp/product/B000FL60AI/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1

attachment.php
Wonder if they sell an RKE module for a reasonable price? Well they do! And only $17.
https://www.amazon.com/gp/product/B006QH9C5A/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

So of course I take the RKE module apart to take a look inside. Pretty good looking PCB with some standard relays, peripheral drive chip and a couple of devices I don’t recognize. The two high current diodes in the upper left by the connector are for the lamp drive and they isolate the left and right side signals. I also notice the antenna wire has no strain relief which I fix with a tie rap. I also tuck a wire loop inside that can be cut to gain more actuation time if your install has pneumatic door locks. I did not like the wire loop hanging out the module just waiting to get hooked on something or broken.

http://www.lotustalk.com/forums/images/LotusTalk_2015/attach/jpg.gif

So just like the comments on Amazon say, the instructions for the module suck. But there are enough comments on Amazon to figure things out easily. Basically the Elise requires a ground signal to be provide to the central door lock module inputs to energize lock and unlock. This function is provided by the RKE module via the relays. So all that needs to be done is to tie the commons of both relays to ground (the yellow and yellow/blk stripe wires). Then the normally open contacts (white and white/blk strip wires) to the appropriate input on the door module input. I also connected the brown wires to the lamp circuits so the lights blink when locked (1 blink) or unlocked (2 Blinks).

Here is a picture of the cobra alarm ATX mating connector with the labels that were extracted from the lotus wiring diagram. The following connector pins will be connected to the RKE module.
Pin 1 = Lock signal
Pin 2 = Unlock Signal
Pin 5 = Right Lamp Circuit
Pin 6 = Battery (un-switched)
Pin 7 = Left Lamp Circuit
Pin 14 = Ground

http://www.lotustalk.com/forums/attachment.php?attachmentid=1096842&stc=1&d=1498012310

http://www.lotustalk.com/forums/attachment.php?attachmentid=1096850&stc=1&d=1498012310

Here is the RKE Module connector routing to the ATX connector with wire functions.

Orange wire = no connection (NC)
White wire = Lock Sjgnal connects to Pin 1 of ATX connector
Yellow wire = Ground for Lock Signal connects to pin 14 of ATX connector
Orange/blk stripe wire = no connection (NC)
White/blk stripe wire = Unlock Signal connects to Pin 2 of ATX connector
Yellow/blk stripe wire = Ground for Unlock Signal connects to pin 14 of ATX connector
Black wire = Module Ground connects to pin 14 of ATX connector
Red wire = Battery un-switched connects to Pin 6 of ATX connector
Brown wire 1 = Right Lamp circuit signal connects to Pin 5 of ATX connector
Brown wire 2 = Left Lamp circuit signal connects to Pin 7 of ATX connector
Green wire = no connection (NC)

Basically you connect the same function wire from each connector together. The three wires on the RKE module identified as ground get connected together and tied to the pin 14 ground wire of the ATX connector. Once you verify everything is functioning the extra wires can be cut off to reduce bulk.

http://www.lotustalk.com/forums/attachment.php?attachmentid=1096858&stc=1&d=1498012437

Here is the module harness connected in the car. Notice the tie wrap installed around the original alarm connector and the ATX connector to keep the connection secured.

http://www.lotustalk.com/forums/attachment.php?attachmentid=1096866&stc=1&d=1498012437

Enjoy the RKE function again with very good range!!
 

Attachments

See less See more
5
#3 ·
I've been known to take a bat to a few pieces of electronics before, so I can relate. I have a home theater PC that is on deck right now!
 
#7 ·
I put mine in a jar of saltwater. Just felt more satisfying to make the death a bit slower.

Thanks for the nice write up.
 
#8 ·
So I decided to do the same thing on my 07 Exige today and I could not find that white harness connector in my car. I pulled out some foam in the passenger cubby to look for it but all I see is this black box thing that is wrapped in sort of a plastic bag. There are wires coming out of it but I don't see the harness plug to disconnect the harness. Can someone tell me if my car is different from the OP's?
 
#9 ·
I'm pretty sure that your 07 Exige is the same as my 06 Elise as far as the alarm is concerned.

Here is a link that may help you with understanding the alarm and connector geometries and getting the alarm wire harness connector unconnected from the alarm module.

http://www.lotustalk.com/forums/f32...rowave-sensor-w-out-flashing-telltale-407577/

The alarm module is inside the bag and the connector plugs in at the top of the alarm housing which makes it tough to get it unplugged because of the lack of space. I shoved the foam towards the windshield as much as possible to gain as much space around the alarm module as possible. Of course you have to open the bag up to get at the connector. There are two plastic latching fingers integrated into the alarm module housing that secure the connector in place.

I used a long straight blade screwdriver to release the locking finger on the left side by pushing it towards the left while simultaneously pulling up on the wire harness with my right hand. It is extremely tight in that space and it took quite a bit of patience to get it done. Once you get the one side unlatched the connector should pivot out without having to release the other locking finger.

Hopefully this info helps.
 
#12 ·
I have wanted to get rid of my alarm since day 1, no need for it at all, but the thought of it scares the hell out of me. I'm not in the least bit electronically inclined, I mean, I'd burn a house down installing a car stereo. But this looks pretty straightforward, might have to try it.
 
#14 ·
Got it to work. Thanks @BigHair for this post. So I just want to clarify to anyone who is doing this pin 14 is the blue wire. Also I wanted to point out that the orange wire on the ATX connector that bighair labeled 12 IGN was a little misleading. I thought this would connect to something but it really doesn't.

Overall it was a pretty simple and straightforward project thanks to bighair. It took me about 20 minutes to unplug the OEM harness and about 10-15 minutes to splice and connect the wires. For someone who knows nothing about electronics, I was able to get it working in under an hour.
 
#15 ·
@rb26dett
Thanx for the good clarifications on the blue wire color for pin 14 and the fact that the Ignition wire is not used. When I labeled the connector, I did it from the wiring diagram in the lotus manual and wasn't sure which pins I would ultimately need; so I just labeled them all to make it easy on myself. But I agree it is misleading...Nice detective work, it will definitely help others.

BTW...you are considered an electronic tech now!

Post your range and impression on operation when you get a chance

Cheers!
 
#16 · (Edited)
Here is a pic of the ATX connector showing the pins 13 thru 24.
Blue wire that was being discussed is shown.
 

Attachments

#18 ·
I just did the mod using the instruction that "BigHair" provided above and it works beautifully. However, I just want to add, make sure you guys connect the wires on step #4 of the instruction that "+TSRAGR" provided at the link below or else you won't be able to start the car. I learned the hard way after putting everything together and found out that the car can't start without those wires connected. I use the paper clip to bridge those two connections and use glue gun to seal it off instead of cut and join those wires.

Thank you so much "BigHair" for sharing the info.

http://www.lotustalk.com/forums/f32...rowave-sensor-w-out-flashing-telltale-407577/
 
#20 ·
Glad to hear that it went well and that the parts are all still available. My install has been trouble free for 3 years now and the RKE range is really good; easily 60 ft. Cheers!


Sent from my iPad using Tapatalk
 
#22 ·
I would like to voice some concern with having ANY Remote Keyless Entry system on these cars, either OEM or aftemarket. If you lock your car with the FOB and something goes wrong you will NOT be able to just use your key for gaining entry. Our keys are not physically connected to the door plungers that go up and down and if the cars are locked by the plungers, either manually or by CDL, you will not be able to unlock the car. Most, if not all, other cars I have ever had could be unlocked by either key or remote. Not true of the Elise.

I choose to just lock my doors with a key so I will always be able to get in! My CDL does work from the switch on the center console but I only use that if I am in a "bad" area and I am inside the car. ;)
 
#24 ·
Bringing this one back again as I am still struggling with what I can and cannot do with my car. I absolutely hate the security system, but I do like the RKE.
First, I have a 2010 with the newer key style. DO the instructions still work compaired to the components in my car. I haven't torn it apart to see what is there.
Second.....do you use the new RKE fobs that come with the kit, or can I still use the button on my key? If this only works with the new fobs, is there an alternate method to remove the alarm, but keep RKE?
Thanks!
 
#25 ·
I’ve been able to wire this module into a completely different car, so I would be hopeful that it would still work in a 2010- wiring harness may be different. The fob matches the module, I don’t see a way to make it work with a your key fob. It’s a great inexpensive upgrade!
 
#26 ·
OK......Seems like a great upgrade, but the 2009+ went to a different key style where the fob is part of the key, so not working with my current key is a huge issue.
Looks like I will continue to research a way to disable the horrible alarm and keep the RKE. I really appreciate your response.
 
#27 ·
Been looking at this post because I'm trying to hook up DRL on my 2005 so I can register it in Canada. I know different topic, BUT...
Can't seem to find a wiring schematic for the ignition/headlights (or at least, ones that still work), so I'm digging.
The right and left LAMP wires? Are we talking about headlights? And which wire would be the ignition?

I have a whole other post trying to find answers for my problem, but apart from actually ADDING "driving" lights, I haven't seemed to be able to figure out hooking up DRL to just the standard headlights.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top