Keyless Entry for 1995

[Rufus]

Hi everyone,

I am a new owner of a 1995 NSX-T - and new to this forum too. Since this is my first NSX, I am not sure whether the 1995 version of this car is supposed to have keyless entry. I have a key fob with two buttons (arm security and disarm security). It looks to be a standard Acura key fob. But when I press it, it does nothing. The red light on the key fob lights up when I press any of the buttons so I think the battery is good. But the car neither unlocks or disables the security light on the door. Does nothing that I can see.

I thought I read somewhere that keyless entry (or remote lock/unlock) was not available until the 97 model, but not sure where I read that. For all you 95 NSX owners, does your key fob lock/unlock your doors. Currently, I need to lock/unlock with my key into the door.

 

[gkantziper]

Hi everyone,

I am a new owner of a 1995 NSX-T - and new to this forum too. Since this is my first NSX, I am not sure whether the 1995 version of this car is supposed to have keyless entry. I have a key fob with two buttons (arm security and disarm security). It looks to be a standard Acura key fob. But when I press it, it does nothing. The red light on the key fob lights up when I press any of the buttons so I think the battery is good. But the car neither unlocks or disables the security light on the door. Does nothing that I can see.

I thought I read somewhere that keyless entry (or remote lock/unlock) was not available until the 97 model, but not sure where I read that. For all you 95 NSX owners, does your key fob lock/unlock your doors. Currently, I need to lock/unlock with my key into the door.

My '95 has keyless entry.

 

[Rufus]

Does your key fob look like this?

And the ARM/DISARM button will lock and unlock your power door locks?

Sounds like something is broken with my keyless entry. Anyone have issues with their keyless entry? Any suggestions on what I might try to troubleshoot this problem?

 

[gkantziper]

Does your key fob look like this?

And the ARM/DISARM button will lock and unlock your power door locks?

Sounds like something is broken with my keyless entry. Anyone have issues with their keyless entry? Any suggestions on what I might try to troubleshoot this problem?

Yes, mine looks like that. Don't feel too bad about it not working. It doesn't work that well anyway because you have no idea the car is locked unless you are close enough to hear it lock or see it lock. No horn or sound feedback. Congratulations on your purchase!

 

[Rufus]

Thanks for your reply. Good to know that there is no horn or sounds feedback - as that might have been the next thing I chase down.

The key fob not working is not a big deal, but my preference is to use a remote to lock and unlock - if only to avoid scratching up the keyhole. Anyway, just trying to keep the car working as it should.

If anyone else has experienced their keyless entry not working, please suggest/share with me what you did to fix it. At this time, not sure what is actually not working...

 

[Old Guy]

Keyless entry was a retrofit / dealer installed option for the first generation NSX. The 'kit' should have come with two remotes so the first thing I would suggest is check operation with both units to make sure there is not a problem with your remote. Just because the red light still lights up does not mean that the battery is OK. It may be a bit of a hail Mary; but, I would try a new battery in the remote to see if that fixes things.

Do the locks operate correctly from the switches on the doors? If the switches do not control the locks correctly the problem may be with the lock control module rather than the keyless unit. The keyless unit sends its open and close commands to the security control unit and lock control unit and if they don't work correctly the keyless entry will not operate.

The controller is installed underneath the glovebox. Does the 1995 have a passenger side airbag? If it does, space constraints underneath the glove box mean that the controller is actually attached to the bottom of the cover below the glove box. If you stick your head down in the passenger footwell and look under the glovebox area you will see it 'tacked' on to the cover (it really was an afterthought). On cars without passenger airbags it might be above that cover; but, it will be in that general area because that is where the interface plugs for the unit are on the body harness.

The first thing to check would be to make sure that the controller is still there (not removed by a previous owner). Check to make sure that the electrical connection / plugs are still secure. Its been about 8 years since I installed mine; but, I seem to recall that there may be an in-line fuse in the wire harness for the controller. You might want to check that fuse to make sure that it is not blown. If the unit is still there and the fuse is not blown, then the controller may require repair. If you are not handy with a soldering iron, I believe the keyless unit is made by either Kenwood or Alpine and a few years ago, I recall that you could still get them repaired by sending it away.

If you do get your keyless entry working, D. Dozier came up with a rather simple modification that you can make that will flash the lights or sound the horn on locking. There is a .pdf describing the modification some where in the Wiki pages.

 

[Rufus]

Thanks Old Guy. I will try all your suggestions. I'm pretty sure my door locks work, but I will test them. I will try a new battery too. Those are easy to check. If those prove to be functional, I will start looking under the glove box.

 

[Old Guy]

I checked my Electrical Trouble Shooting Manual this am (because the service manual provides no info on the keyless systems) and confirmed that the keyless controller unit does have a 3 amp ATC style in-line fuse in the wiring harness attached to the controller.

 

[Rufus]

Hi Old Guy,

Thanks for your suggestions. I did check the batteries and swapped them out. That did not solve the issue. I also checked the power lock system. Works fine. Lock and unlock buttons inside the car lock/unlock properly.

So it seems like perhaps the main unit may be the issue. I did not have time to look into the unit underneath the glove box, but will try to look at that in the next few days. I will look for that fuse. Would be nice if it's just the fuse being out.

 

[Old Guy]

Hi Old Guy,

Would be nice if it's just the fuse being out.

That would be like Christmas in May .:smile:

 

[Chase_acura]

Possible fuse blew on the keyless harness, look under the glove box for the unit.

 

[Rufus]

Hi Old Guy, Chase_acura,

Not sure what I should be looking for? Is the unit with the fuse in that small black box? Do I unscrew everything to get it off so I can access the fuse? Or am I looking in the wrong place?

Also, you can see a grooved silver plug that goes into the unit. I though that the fuse might be inside if I unscrew the silver plug. But there wasn't. I screw that plug cover back. But after this experiment, I start getting the EPS light. Wondering if you knew whether that black box has anything to do with the power steering.

Thanks.


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[Old Guy]

Your image doesn't display so I can't comment on the 'black box'.

The in-line fuse holder is in the wiring harness that connects between the keyless unit and the car wiring harness. It has one of the those plastic ATC blade style fuses and should be very obvious. You don't need to take the keyless unit apart to access the fuse. As I recall, there is a round RCA like plug on the keyless unit with a single wire attached to it. That is the antenna for the keyless unit.

The keyless unit has no interaction with the electric power steering. If you have disturbed the EPS controller, you are looking in the wrong place for the keyless unit. Post #3 in this thread has a picture of the keyless unit so you know what you are looking for.

http://www.nsxprime.com/forum/showt...ss-entry-system-remote?highlight=keyless+unit

Use the service check connector to retrieve the error code for the EPS unit. The error may be related to you messing around under the dash or it may be totally unrelated.

 

[Rufus]

Thanks.

It looks like the photo did not attach well to the post, but I looked at the photo from the other thread and that is in fact the black box I am referring to. It seems that it was the antenna that I unscrewed to see if the fuse was inside there. So I guess the fuse I am looking for is on the harness that comes out of that box and into the main body of the car. I will look for that. I didn't notice a fuse, but there are many harnesses in that area and I might have missed it.

 

[Rufus]

As for EPS, I asked some questions in another thread regarding issues other people might have had with EPS. I tried reseting the EPS by pulling the fuse (unscrewing it off) as I thought one other owner had said they did to reset the EPS (assuming nothing is wrong with EPS and my low car battery made it shut off), but that did not make the red EPS light go away. Seems like I might actually have a ESP issue. Wondering what the common cause of this is.

I am unfamiliar with the NSX (not a mechanic or service tech). Not sure if you need some instrument to check code via the service check connector. If so, I don't own one. Are they costly. Should every NSX owner have one?

 

[Old Guy]

I tried reseting the EPS by pulling the fuse (unscrewing it off) as I thought one other owner had said they did to reset the EPS (assuming nothing is wrong with EPS and my low car battery made it shut off), but that did not make the red EPS light go away. Seems like I might actually have a ESP issue. Wondering what the common cause of this is.

I am unfamiliar with the NSX (not a mechanic or service tech). Not sure if you need some instrument to check code via the service check connector. If so, I don't own one. Are they costly. Should every NSX owner have one?

I am confused about your reference to resetting the EPS controller by unscrewing off the fuse. There is no unscrewing involved. The EPS controller (and the ECU) are reset by removing the clock fuse in the main fuse box up front for 10 seconds. Retrieve the stored trouble codes before you do the reset. There are a number of things that can cause the EPS controller to set an error condition and illuminate the EPS light. Low voltage is just one of them.

No special tool required to access the trouble codes. An un insulated paper clip will do just fine. Review this thread which also discusses an EPS problem to find the location of the service check connector.

http://www.nsxprime.com/forum/showt...roblem-but-no-codes-are-coming-up-Please-help!

You will need to get a copy of the service manual (links to it are in the Prime Wiki) to review the retrieval process and get a list of the error codes and causes.

 

[Old Guy]

Thanks.

It looks like the photo did not attach well to the post, but I looked at the photo from the other thread and that is in fact the black box I am referring to. It seems that it was the antenna that I unscrewed to see if the fuse was inside there. So I guess the fuse I am looking for is on the harness that comes out of that box and into the main body of the car. I will look for that. I didn't notice a fuse, but there are many harnesses in that area and I might have missed it.

When you detach the keyless unit from the cover, there will be a wire harness that goes from the plug on the keyless unit to plugs on the vehicle harness. The in-line fuse is in that harness. The fuse should be quite visible when you lower the keyless unit. I think the fuse is located probably 5 - 7 cm along the harness from the plug that goes into the keyless unit; however, its been 7-8 years since I installed mine so I may be off on the exact location. I also have a 2000 and Honda changed the harness design sometime during the early production run so yours may be slightly different.

 

[Rufus]

Thanks for the suggestions and instructions. I pulled the clock fuse this time and it reset the EPS. The EPS light is gone and power steering is back. So it seems like the EPS system is fine since it's working as it should. It seems like an electrical glitch - probably due to my dying battery.

So two more questions:
1) Battery - I can see my voltage meter dipping from the usual 14V down to 12V and bouncing back up. Hopefully this is just an indication that the battery is weak and that when certain systems pull current, it's dipping the battery. My plan is to replace the battery. When I purchased this car, it came with a trickle-charger that was attached to the battery and sits inside the front area next to the spare wheel. Is this common among NSX owners? Never owned a trickle-charger before. Not sure if people hooked it up when needed or it's normal for it to stay in the car. I ask because I wonder if the trickle-charger is depleting the battery too when not plugged in. I have been driving my car about once a week, sometime I might go two weeks between drives. Not sure if I really need a trickle-charger since it's not sitting idle for long periods of time. Any thoughts. Just wondering when I change the battery, if I should just leave the trickle-charger out.

2) Back to the original question about keyless entry. So I found the harness and traced it to these "fuses." Not sure if this is what you are referring to. Here is a photo (with one of the fuse out. They look like diodes...)

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Here is the fuse by itself. Is this what might have burnt out and how can you tell? Cannot tell visually...

<img id="<B4067B4C-EDAE-4DA2-A399-FA45C12D4555>" src="blob:http://www.nsxprime.com/4ace063d-63d8-40ce-bb6c-add86de537a1" alt="Image 5-27-19 at 10.26 PM.jpeg" apple-inline="yes" class="Apple-web-attachment Singleton" style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px;">

Please confirm if I am going in the right direction here.

 

[Rufus]

Also, in an attempt to see if the fuse is visible if I detach the module, I pulled it off. It's a completely enclosed box so that did not help - I thought it was an open box with fuse visible when removed). But what I was able to confirm is that the number on the module matches that of the number on my key remote. This was probable, but at least I can cross off the module and remote not being paired as being the issue.

<img id="<42D5F7AD-5510-4115-B057-E91282FA4A64>" src="blob:http://www.nsxprime.com/7f73ca3b-897e-407f-8b34-8ef9ee88d603" alt="IMG_3231.jpeg" apple-inline="yes" class="Apple-web-attachment Singleton" style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px;">

Unfortunately, when I unscrewed the two screws that held this unit attached to the bottom side of the glove box, I did not realize the nuts on the other side were loose nuts, not a fixture that you screw into. So once I unscrewed the unit, the nuts moved away and I cannot screw the unit back onto the bottom side of the glove box. I think I need to now take off the bottom plastic piece that the unit was attached to and screw the unit back on with that plastic piece off so that I can access both sides of it. But my attempt to try and pull that plastic piece off was unsuccessful. I removed two screws just under the glove box door opening that would allow me to remove it, but it did not. I decided not to remove any more screws since I really do not know how this section of the car is assembled and did not want to risk damaging anything. If there are instructions on how to attach the security unit box back on the underside of the glove box, please provide.

Thanks.

 

[drew]

Go through this thread: it will show you everything you need to know:

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

 

[Old Guy]

So two more questions:
1) Battery - I can see my voltage meter dipping from the usual 14V down to 12V and bouncing back up. Hopefully this is just an indication that the battery is weak and that when certain systems pull current, it's dipping the battery. My plan is to replace the battery. When I purchased this car, it came with a trickle-charger that was attached to the battery and sits inside the front area next to the spare wheel. Is this common among NSX owners? Never owned a trickle-charger before. Not sure if people hooked it up when needed or it's normal for it to stay in the car. I ask because I wonder if the trickle-charger is depleting the battery too when not plugged in. I have been driving my car about once a week, sometime I might go two weeks between drives. Not sure if I really need a trickle-charger since it's not sitting idle for long periods of time. Any thoughts. Just wondering when I change the battery, if I should just leave the trickle-charger out.

2) Back to the original question about keyless entry. So I found the harness and traced it to these "fuses." Not sure if this is what you are referring to. Here is a photo (with one of the fuse out. They look like diodes...)

<img class="Apple-web-attachment Singleton" id="<CC882675-87B2-4777-A96B-59932F3BB486>" style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; caret-color: rgb(0, 0, 0);" alt="Image 5-27-19 at 10.26 PM.jpeg" src="blob:http://www.nsxprime.com/72edd3e0-ed38-45d2-9485-e3eb7f38a9e5" apple-inline="yes">

Here is the fuse by itself. Is this what might have burnt out and how can you tell? Cannot tell visually...

<img class="Apple-web-attachment Singleton" id="<B4067B4C-EDAE-4DA2-A399-FA45C12D4555>" style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; caret-color: rgb(0, 0, 0);" alt="Image 5-27-19 at 10.26 PM.jpeg" src="blob:http://www.nsxprime.com/4ace063d-63d8-40ce-bb6c-add86de537a1" apple-inline="yes">

Please confirm if I am going in the right direction here.

With respect to the battery, when the key in in the on or Acc position; but, the engine is not running the voltage should read 12 volts as long as you are not running anything significant like a fan or headlights. If the voltage is down around 10 volts or less you have a dead cell(s) and its time for a new battery. If you switch the headlights and interior fan on (engine not running) and the voltage drops significantly (10 volts or less) you could have a dying cell(s) or high internal resistance. In all of these cases its time for a new battery. However, stretched battery cable clamps are a chronic problem on the NSX caused by over tightening of the bolt on the clamp. Put a plastic glove on (for acid protection) and see if you can twist the clamps on the battery posts. If you can twist them this means the clamps are typically damaged. You can make a temporary fix by purchasing battery post shims; but, the best solution is to plan to replace the clamps. Loose clamps can result in high resistance and low voltages which can lead to starting problems and EPS problems.

The NSX has older school electronics with fairly high parasitic loads. Some owners have installed the smaller battery used in the Zanardi (I think its a 51R - same battery as used in later Civics and RSX) to save weight. The parasitic loads may kill this battery fairly quickly. With the correct battery in good condition the NSX should be good for two weeks or more. Get the correct sized battery and you will definitely be OK for weekly operation without a battery tender.

When the engine is running, the voltage should be pretty much rock solid around 14.2 volts. My voltmeter might twitch when I switch the air conditioning on at idle; but, not by much. If the voltage is dipping significantly when the engine is running, the alternator may be wearing out (brushes starting to provide hit and miss operation) or you may have a loose connection(s) on the alternator or those nasty clamps on the battery may be screwing things up. Check the electrical connections first before chasing the alternator as a problem. The ground cable between the engine and the body can also cause problems as can deterioration of the ground cable between the battery and the body. Unfortunately, some of that stuff really requires a hoist to inspect.

If you are checking for loose connections by wiggling and pulling on things or using a wrench to test bolt tightness its best to disconnect the negative terminal on the battery. You don't want to have a wire slip off or a wrench slip and contact the body creating a short circuit. Safety is a good thing!

That link provided by [MENTION=5430]drew[/MENTION] provides good information, particularly details on removal of the components under the glove box. The thread covers the 1991 system. I think the keyless controller is the same; but, the wiring harness on the 1991 is definitely different than on the later cars so use that information with caution. On post #41 of that thread you will find some very nice pictures provided by [MENTION=13463]UnhuZ[/MENTION] which shows the in-line fuse and its holder and yes, there are a couple of diode 'things' that also look like in-line fuses. If you look at the big photo of the fuse provided by UnhuZ you can see the fusible element in the fuse (S shaped wire). If that wire is broken or missing then the fuse is open and needs to be replaced.

In order to access the in-line fuse you normally need to get that bottom cover off. If you were able to get at the fuse holder and diodes without removing the bottom cover I think that would require some significant pulling on the harness and things might have come loose on the body side of the harness. You definitely need the bottom cover off and the glove box out to check the connections on the body side of the interconnecting harness.

Does your 1995 have an OBDII port - I am never sure whether some or all North American market 1995 NSXs received OBDII? It will be mounted at the edge of that bottom cover on the left with a little plastic cover over it. The OBDII connector plug should slide up out of its holder as you drop the cover to allow removal of the cover; but, the plug needs a little persuasion with the sliding. The OBDII connector is not shown in the 1991 instructions; but, needs to be detached from the cover to get the cover out of the way. As I recall, in addition to the 2 screws holding the cover there are three clips along the same edge of the cover holding it in place. You will need to gently pop these clips loose by pulling down on the cover. I have a soft plastic wedge (looks like a very fat chisel) that is specifically made for popping things out like this while avoiding damage to the plastic parts.

Your pictures do not attach. Try using the Go Advanced function below the reply window. This will pull up a new reply window and towards the bottom you will find a Manage Attachments button. This will allow you to copy files from your device and have them hosted by the Prime server. Its takes a few steps; but, it does work because whatever you are doing to attach files does not work.

 

[Old Guy]

P.S.

Unless you are located close to a dealership with a known good NSX tech or are close to Larry B. or SOS or one of the other known NSX specialists, you really need to get a copy of the factory service manual and familiarize yourself with it. The NSX qualifies as rare and >95% of auto techs will have never worked on one or even seen one before. You don't want your car to be a training ground.

The NSX is exceedingly durable. But, your car is close to a quarter century old and you should expect that increasingly things are going to start going wrong. The service manual is going to be your survival guide if you don't live close to a competent NSX tech.

If it turns out that your keyless master is truly dead, you might be able to find a suitable replacement in a salvage yard from one of these cars

92-95 Legend
96-97 TL
92-94 Vigor

The controller is the same; but, the part number is different because the interconnecting harness is different.

 

[Rufus]

Thanks everyone for your help. I was able to fix all the issues I've been having recently. I replaced the car battery today. I think it was my low battery that triggered the EPS light. I reset the EPS (thanks Old Guy & laclipz) and everything seems to be working now. I took my car out for a drive today after the battery change and the voltage meter on the dash no longer jitters between 12V-14V. It now seems to be lock at a bit above 14V. EPS light is off and power steering is working as it was before the light had come on.

As suggested, I decided not to connect the battery tender to the battery. It's an on-board tender, so it's still in the car, but I disconnected the plugs. Easy to plug back in if I need to charge the battery in the future. Hopefully, since I am driving the car more often than the previous owner, the battery will not be an issue (the other battery was only a bit over 2-years old, but sat a lot during those two years).

Also, Old Guy, thanks for your suggestions on checking the 3A fuse connected to the keyless entry module. I followed the link that [MENTION=5430]drew[/MENTION] provided and read the instructions to take off the underside of the glove box. I was able to then locate the 3A fuse and sure enough, it was blown. I replaced the fuse and everything is functional. I now have keyless entry. I'm grateful that it was only the fuse and not the main unit or even my remote that was not functioning. Lucky.

I really appreciate everyone's help. I'm a new NSX owner and new to this forum. This is a great resource and a helpful community for NSX owners. Thanks all.

 

[Old Guy]

I was able to then locate the 3A fuse and sure enough, it was blown. I replaced the fuse and everything is functional. I now have keyless entry. I'm grateful that it was only the fuse and not the main unit or even my remote that was not functioning. Lucky.

Well Christmas really did arrive for you in May (or June). Fuses usually blow for a reason meaning the underlying problem is someplace else; however, they can also age out from heat cycling if operated close to their limits or fail from vibration fatigue. Whatever the reason, go with the positive results.

Nice to hear of a positive outcome.

 

[Rufus]

Looks like this issue was noted on a service receipt I found from two owners ago - that keyless entry was not working. But I guess nothing was done about this until now. The guy that sold it to me mentioned that the keyless entry never worked for him. Hard to say why the fuse blew out in the first place. It seems like it's not a common thing.

Well, hopefully it will work for a long time. If the keyless entry goes out and the fuse is blown again, at least I know the issue is further upstream. The experience was good - a reason to dig in a bit to get to know this car a bit better. I'm sure this will be part of the experience of owning a first-gen NSX.