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DIY: Aftermarket Keyless Entry System with Factory Alarm activation

Joined
7 May 2018
Messages
993
Location
San Jose
I’ve had the factory keyless for over a year now and was frustrated at the fact that it didn’t flash the lights with lock/unlock and it didn’t remote pop the trunk. After a ton of research it seemed like going aftermarket as the only option. However, I wanted to be able to use the factory alarm. I also wanted to be able to plug in using the factory connector.

There were a lot of threads on Prime with lots of good info but nothing definitive. With a lot of help from @drew and @Old Guy , I was finally able to integrate an aftermarket keyless entry system using the factory keyless connector. This set up also arms and disarms the factory alarm. Keep in mind this was done on my 99. I believe it should be the same for 93-03.

*EDIT* see post#9 for diagram if you have a 91 or 92

Materials Needed:
1 Aftermarket Keyless Entry system
2 1N4001 Diodes

Optional:
12 pin HD 090 Male Connector available here:
http://www.cycleterminal.com/hd-series.html
It’s Sumitomo part number 6098-0252

If you elect to use the above connector, you’ll also need a crimper like this if you don’t already have one:

https://www.amazon.com/gp/product/B017JU20Z6/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1


You’ll need to reference the wiki to locate the factory connector:
http://www.nsxprime.com/FAQ/DIY/keyless_entry.htm
It’s under the glove box. It’s a 12 Pin Green Connector.


For the keyless module I bought a fairly basic unit but you can get a higher end Viper if you want. My instructions are fairly generic so it should work for any aftermarket keyless system.


This diagram shows which wires you’ll need to connect to. You really only need six basic connections. The connector is optional but makes a cleaner install. You can always tap the respective wires on the factory connector.

Keyless Schematic v2.JPG
View attachment 164476


To arm/disarm and lock/unlock you’ll need a negative (-) signal from your keyless system.
Once you’ve identified/configured the lock wire, you’ll need to split it and insert into both pin #5 and #6 for Arm and Lock respectively*. Split the unlock wire and insert to pin #10 and #11 *

*IMPORTANT – You must install two diodes as shown in the diagram to isolate the arm and disarm signals. If you don’t, when you lock and unlock using one of the door buttons you’ll also arm and disarm the vehicle. In other words, if someone breaks your window and unlocks the door using the button on the door, your alarm will disarm. The alarm will go off if they break your window and lift up the unlock door pin though.

Constant 12+ volt power wire will go to pin#8

Ground (-) will go to pin#12.

Here’s my connector / harness connected to the factory KES plug.


IMG_20200406_175359.jpg

IMG_20200406_175219.jpg

While the factory KES module is mounted under the glove box, the aftermarket KES I purchased was small enough to fit above the Power Door Lock Control Unit (PDLCU).

Optional: Flashing Lights upon arm/disarm (if your aftermarket KES has this feature). This feature was not available with the factory KES. This particular unit sends a (+) signal for the lights. I ran a separate wire to tap into the Red/Black wire at the Grey Plug below the Driver’s dash. I forgot to take a picture but once you remove the driver’s knee bolster, it’s pretty obvious. If your unit sends a (-) signal then you’ll need to hook up a relay in order to flash your lights.

Optional: Trunk release (if your aftermarket KES has this feature). This feature was not available with the factory KES. You will need to run a separate wire for the trunk release. Everything I’ve read said to tap into the White/Black with Silver Dots wire which is located at a Blue Plug below the Driver’s dash. I was able to see the plug but after an hour of working upside down on my back, I gave up trying to access it. I suspect you pretty much have to take apart the dash to gain access to it. If someone has done it without removing the dash please share for future reference. The alternative was to make a connection at the trunk. You can splice into the Cell Phone DIN cable or CD changer cable if you’re not already using them. This way you can avoid having to run a wire through the engine bay. I tripled up the wires as they’re very thin. I ran the trunk release wire from the KES through the center console to the rear bulk head where it connected with the corresponding wires of the CD Changer Cable.


A few notes: I didn’t hook up switched power because I didn’t see any benefit. The factory keyless still locks and unlocks the doors with the ignition on. I also, didn’t plan on using the auto door lock when moving feature or the auto window roll up feature of the KES. My KES also came with a flashing LED light which I didn’t use either.

When you press lock, the doors lock and the factory alarm arms (flashing LED at driver’s door). When you press unlock, the doors unlock and the alarm disarms.

Keep in mind that you should press unlock before holding the trunk release button for 3 full seconds to pop the trunk. Otherwise you will set your alarm off.

The factory alarm does not fully activate until about 15 seconds after arming. The LED on the driver’s door flashes every second during this time. Once the LED flashes once every two seconds, the system is armed.

OE vs Aftermarket.

With the aftermarket unit, it does not let you know if a door is not fully closed. It will still lock the doors when you press the lock button. But the alarm will not be armed. You’ll need to be aware of this if you had a factory keyless and was used to the fact that the doors won’t lock if both doors are not fully closed (or trunk open, or hood open, etc.). This after-market unit also does not automatically lock the doors after you press unlock and don’t actually open one of the doors within 10-15 seconds (a feature of OE).

I’m happy that the lights flash with lock and unlock and I enjoy having a remote trunk release. Funny how the most minute of features can make such a difference.

Thanks to all before me that had attempted something similar and shared your knowledge.

The main take away is that if you want to activate the factory alarm, you’ll need to tap into the respective arm (BRN) and disarm (GRY) wires as well as lock (GRN/WHT) and unlock (WHT/YEL) on the factory connector. Be sure to isolate the arm and disarm wires with diodes. The factory alarm will NOT arm if the doors are unlocked.

Finally, if you have a 91 or 92 these threads should be helpful:

http://www.nsxprime.com/forum/showthread.php/140311-91-92-Keyless-Solved

http://www.nsxprime.com/forum/showthread.php/109139-91-keyless-entry-the-truth

Here's a video of it in action:

https://www.youtube.com/watch?v=-sXbcPEV-DM
 
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Awesome writeup !! I need to redo my PKE system to use that factory connector, this is soo much cleaner.

Regarding below:
Optional: Flashing Lights upon arm/disarm (if your aftermarket KES has this feature). This feature was not available with the factory KES. This particular unit sends a (+) signal for the lights. I ran a separate wire to tap into the Red/Black wire at the Grey Plug below the Driver’s dash. I forgot to take a picture but once you remove the driver’s knee bolster, it’s pretty obvious. If your unit sends a (-) signal then you’ll need to hook up a relay in order to flash your lights.


When I was working on my PKE system I had problem that only one side of side markers would blink, so I install two relays to have both sides blink and not back feed to circuit but when I disarm one side is off sync by like a millisecond. My side markers are LED's and it's little noticeable. Is there a single wire to activate all side markers?

Thanks.
 
Awesome writeup !! I need to redo my PKE system to use that factory connector, this is soo much cleaner.

Regarding below:
Optional: Flashing Lights upon arm/disarm (if your aftermarket KES has this feature). This feature was not available with the factory KES. This particular unit sends a (+) signal for the lights. I ran a separate wire to tap into the Red/Black wire at the Grey Plug below the Driver’s dash. I forgot to take a picture but once you remove the driver’s knee bolster, it’s pretty obvious. If your unit sends a (-) signal then you’ll need to hook up a relay in order to flash your lights.


When I was working on my PKE system I had problem that only one side of side markers would blink, so I install two relays to have both sides blink and not back feed to circuit but when I disarm one side is off sync by like a millisecond. My side markers are LED's and it's little noticeable. Is there a single wire to activate all side markers?

Thanks.

I made a single connection at the Red/Black wire at the Grey Plug below the Driver's dash. This wire is the parking light wire. When arm/disarm, the parking lights all flash in sync. It sounds like you tapped into separate right and left signal lights using relays.
 
Oh, that makes sense. Yea I went the hard way and wired each side lol.

This must be the cable you were referring. It’s gray plug with red/black wire.

20f66d4578c559444605a1119e5d915b.plist



Sent from my iPhone using Tapatalk Pro
 
Oh, that makes sense. Yea I went the hard way and wired each side lol.

This must be the cable you were referring. It’s gray plug with red/black wire.


Sent from my iPhone using Tapatalk Pro

Looks like it. Its just left of the steering column.
 
With the aftermarket unit, it does not let you know if a door is not fully closed. It will still lock the doors when you press the lock button. But the alarm will not be armed. You’ll need to be aware of this if you had a factory keyless and was used to the fact that the doors won’t lock if both doors are not fully closed (or trunk open, or hood open, etc.). This after-market unit also does not automatically lock the doors after you press unlock and don’t actually open one of the doors within 10-15 seconds (a feature of OE).

That is a sanitary installation with the plug from Cycleterminal and I like sanitary. I intensely dislike those squeeze style T tap connectors. They are bulky which makes them a hassle to fit in the tight spaces on the NSX. They also inevitably damage strands in the tapped wires.

The OEM keyless unit has a direct input from the passenger and door activated dome light control switches. That is how it generates the re-lock / re-arm function if you do not open the doors within X seconds. Pure keyless units such as the Viper 211 (and I expect others) have a similar function that they refer to as a passive mode. The passive mode detects a failure to open the door (using what they call a dome light supervision circuit) within X seconds which then generates one or more of the following; re lock, re arm, activate starter kill. Some like the Viper 211 re lock; but, do not appear to re arm. In the case of the Viper if you locked the car with the remote; but, opened the car with your key its not clear that the Viper won't get the message that the alarm system should be disarmed; however, I think the OEM security system would get that message from the door key switches even if it didn't get the message from the keyless unit.

I think the Viper 211 is out of production; but, there are newer equivalents that appear to be in the $70 - $100 range. Significantly more than what you paid; but, much less than the now unobtainable OEM keyless unit.
 
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Thanks for sharing, especially the parking light wire. Been missing the flash greatly.
Will try to hook mine up soon!
 
Finally figured out the 91-92 connections with help from @drew . For 91-92, there's an 8 PIN harness in the car which you will make four basic connections: Power, Ground, Lock, and Unlock. You can use the 8 PIN HD-90 Male Connector found here:

http://www.cycleterminal.com/hd-series.html

Again you'll need to split the the Lock and Unlock wire from the KES with the Arm (Red) and Disarm (Yellow) wires being plugged into the 16 PIN SCU connector as seen in the factory instructions. You'll need to use 22AWG wire. Be sure to install two diodes.


91-92 KES PINs.JPG



For the Red (arm) and Yellow (disarm) wires referenced in the factory instructions, you'll need two Female AMP Multilock 40 terminals found here:

Part# 175062-1


http://www.cycleterminal.com/amp-multilock-070.html#Multilock040

attachment.php
 
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Knowledgebase:

The connector in question is C444 and has 18 terminals. The parking and signal lights both go through this connector.

The RED/BLK wire is the parking lights. It should be noted that this connection requires full current to directly drive all the parking lamps (best that I can tell from the ETM)

The BLU/YLW (18P-4, Right) and BLU/GRN (18P-5, Left) are the turn signal and hazard lights, including the side marker lamps. These connectors activate relays and do not require much current.


On RHD cars this connector is located on the driver side, under the steering wheel, and is clipped to the HVAC box (next to the drivers left knee)

On LHD cars this connector is located on the right side of the driver footwell near the HVAC box.
 
[MENTION=34822]I_M_Legend[/MENTION] awesome info thanks!!!! can you share what aftermarket unit did you use?
 
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