NSX FAQ

Electrical Accessories

Tips on Installing Electrical Accessories

[AW] A couple suggestions for people anticipating the installation ofafter-market electrical accessories (radar detectors, driving lights, radios, etc.) 

     
  1. Honda has provided four "Option Connectors" C910 through C913 afew inches      above the fuse panel located to the left of the driver'sleft leg. Each of these provides      "12V" power under one of the following conditions:
     
  •    All the time (careful with this one; you can run your battery down) 
     
  • When the key is in the IGN position 
    •  
  • When the running or headlights are on 
    •  
  • When the key is in the ACC or IGN position 
 
I remember only that the last one is C913 and is the one located farthest to the front    of the car. I'll supply the relative locations of the other three in a subsequent post.
     
  1. A commonly available crimp-on connector that works with these Option Connectors (which      are similar to 1/4" male quick-disconnect terminals) is found in Radio Shack 64-3049      ($1.49) which includes two each of both male and female in both 22-18 and 16-14 gauge wire      sizes.
    2.  
     
  2. It's easier to see and access the Option Connectors if you remove the upholstery panel      that runs beneath the steering column, and contains one of the interior lights. This panel      removes easily by removing a phillips-head screw at each end. You can leave the interior      light connected because there is enough wire on it to let the panel fall to one side.
    3.  
     
  3. Many temporary accessories like radar detectors and radios are designed to be powered by      a "CLA" (Cigarette Lighter Adapter) which is intended to be plugged into the      socket of the Cigarette lighter. My objections to this arrangement include that these are      a) bulky and b) unreliable, and c) there is only one socket in the car so if you have more      than one device you're left to do something even more unreliable and bulky. According to a      (so far) unverified source from a Usenet news group I follow, the American Radio Relay      League (ARRL) is supporting a standardized connector for 12V devices. The purpose of this      is to provide easy interchangability between various equipment in disaster situations,      etc.
    4.    
       The connector they have specified is a 2-pin molded nylon connector (the common name is      "Molex") These are available at Radio Shack under PN 274-222. Both halves are      insulated, the connectors have "ears" to allow chassis mount if desired, and      they are rated at 8 amps.
       
       Recommended configuration is to use the smaller (inner) connector on the power _source_      with female pins. The outer connector goes on the power user (detector, radio, etc) and      should be assembled with male pins. Positive is the "pointy" end of the      connector. I  recommend soldering the pins for best connection.
       
       I'm going to wire into my cars a small plastic box (like Radio Shack 270-220) located in a      discrete but accesible place with 3 or 4 of these connectors pre-wired to C913, and then      convert all of my CLA-equipped accessories to use this scheme. That way I'll have an easy      and reliable way to plug in temporary accessories and not have to fiddle with the      cigarette lighter each time. My plan is to simply cut off the CLA from each device and      replace that cut with a male and female connector appropriate wired. That way I can use      the accessory in a cigarette lighter *or* in my ARRL-standard-wired cars.

12 Volts DC Source On Firewall

[MBA – 2000/7/24] A safe, and common source, is the black with yellow tracer that goes to all or most of the small control units behind the seats. Its good for 1 or 2 amps without a fuse change, which is enough for most if not all electronics. (fog lights and amps not included) Do not use the 20 g (.8mm) b/y that goes to the main ECU, rather the 18 or 16 (.75 or 1. mm) g.

Firewall Wire Passthrough

[AW] Richard Relph asked a while back about a good place to pass a wire (in his case the coaxial antenna cable for his non-factory cell-phone) from the engine compartment to the passenger compartment.

Alex Vizcarra reminded us privately that you can punch a small hole throught the grommet through which the main harness passes just in front of the air cleaner on the left side of the engine compartment. Access to the passenger compartment side of that grommet requires removing the left-side lower trim panel (the curved one below where the shoulder belt passes through.

I happened to have my interior apart today and I think I found an even better spot. It’s on the right (passenger) side of the car and here’s how to find it. Just forward of the alternator is a large bracket running at about a 45 degree angle to vertical, at the top of which is attached a cast aluminum and heavily finned "box" about 2" square. Forward of and below that bracket is a plastic plug which removes easily and exposes a ~1" hole through which one could pass all kinds of interesting cables. This hole leads to the interior right behind the right-side lower trim panel.

There are a couple advantages to using this hole rather than the harness grommet Alex mentions:

     
  1. It's easier to remove the right-side trim panel, since you don't have to mess with the      engine cover release lever.
    2.  
  2. You can drill whatever hole or opening in the plastic plug and seal it all up with      silicone rubber, etc., without having to go anywhere near any pre-existing wiring      harnesses. Or you can replace it with a store-bought rubber gromeet suitable for whatever      cable your routing.
    3.  
  3. I believe that it's (much easier to get to from the engine-compartment side than the      corresponding area on the left side of the car, since there isn't nearly as much      paraphernalia in the area..

Do It Yourself