Preparation of the Black Boxes ========================================================================== Preparation of the Black Boxes A look inside a black box. The first thing you need to do is prepare the black boxes as per my wiring diagram. See the notes in the previous sections on parts and procedures on different ways to do this. Modifying the Project Enclosures -------------------------------------------------------------------------- For the relay to fit properly, the boxes must be modified as follows: * The four standoffs on the bottom of the box must be removed. I tried a sharp knife, rotary (dremel type) tool, and drill. All seemed to work equally well, but the rotary tool was the quickest. If using a drill, be sure not to drill through the bottom of the box. Any burrs or flashing should be removed with sandpaper. * The tall screw posts on one end of the enclosure must be shaved down to let the relay lay flat in between them. Carefully shave these posts equally with a file or knife, checking the fit of the relay frequently. It should slide freely all the way down to the bottom of the box. Be careful not to cut too far into the posts (down to the screw threads.) * Trim two of the beveled screw holes on the plastic lid, so the lid will fit snugly onto the box with the relay installed. * On the opposite end of the box, drill two 5/16" holes so there's about 1/4" of plastic remaining between the holes. Be careful not to drill into the long screw posts. Sand the edges of these holes smooth, the sharp plastic edges or burrs will shred the electrical tape and wiring insulation. Wiring in the Relay -------------------------------------------------------------------------- For this step, I will refer to the two connectors as 5M1F (five male, one female) and 1M5F (one male, five female). The 5M1F connector will be connected to the chassis side connector in the car, and the 1M5F connector will be connected to the headlight actuator. To determine the terminal numbers on the relay, take the second one and place it with the terminals up, so you can see the markings. Once you start installing wires, the markings become obscured, and using the drawing on the other end of the relay can be misleading. Make the second black box before closing the first to compare the two. Trim the wiring connectors to the length decided upon (+ about 1") when determining where to put the black box. Trim the yellow and green wires about 1/2" shorter than this. Cut the white wire on the 1M5F connector about 2" from the connector. This wire is not used. Using some of the scrap brown wire (about 1 3/4") make a jumper to be installed on the relay. Tin the ends, bend the ends into "U"'s and crimp but DO NOT solder this jumper onto terminals 3 and A of the relay yet. For the remainder of this procedure, the parts should be laid out as follows: The box should be oriented with the two wiring holes on the left. The relay should have the A & B terminals closest to you. The 5M1F wires will be run through the top hole (farthest from you) in the box, and the 1M5F wires will be run through the bottom hole. Move the parts as necessary to facilitate soldering, but after each wire, place the components back in this position to keep everything straight. Strip and tin the brown wire on the 5M1F connector and run it though the upper hole in the case. Bend it into a "U", and crimp it onto terminal 3 with the jumper installed above. Solder the connection. Strip and tin the red wire from the 1M5F connector, run it through the lower hole, crimp and solder it to terminal 5. Strip and tin the brown wire from the 1M5F connector, crimp it next to the jumper on terminal A, and solder it in place. Strip, tin, bend, crimp and solder the remaining connections in this order: * Red, 5M1F, Top hole, Terminal 1. * Blue, 1M5F, Bottom hole, Terminal 6. * Blue, 5M1F, Top hole, Terminal 2. * White, 5M1F, Top hole, Terminal B. Re-check your wiring (i.e. connector/color to terminal number.) Look closely to ensure no solder connections between terminals are unusually close (< about 1/8"). If they are, the terminals can be carefully bent apart to provide more space, or a piece of electrical tape can be inserted between the terminals. All connections should be very tight (no wires can wiggle), and the wires should run directly away from the relay (not off to the side.) If any of the terminals are loose in the relay housing (probably from an overheated connection), chances are good that the relay is damaged and must be replaced. Run the green wires through their corresponding holes, strip about 3/8" from each, splice, solder and tape the connection. Do the same with the yellow wire. Tape the yellow and green splices together. Pull the connectors out of the box until the relay sits down flush in the bottom. The plastic cover should fit snugly now (make sure the notches you cut in the top are aligned correctly.) Tightly wrap electrical tape along the wires from each connector as far up wires (toward the box) as possible. Gently push the wires into the box (with the relay seated properly) and install a tie wrap tightly around each set of wires where they exit the box. This can be tricky, but is done to prevent an accidental yank of the wire from damaging the relay or silicone sealant. Lift out the relay, and put a piece of foam tape on the under side, also put another piece on the top. You don't need to use both sticky sides of the tape (leave the plastic coating on one side.) The relay fits so snugly, it won't be bouncing around inside the box. Put a generous amount of silicone aquarium sealer around the holes that the wiring goes through to make a watertight seal. Allow this to dry thoroughly. Be sure not to let it interfere with the top (trim any excess away.) With the amount of water blowing around in the vicinity of the headlights during driving in the rain, the black boxes MUST be watertight! Put a piece of foam tape on the top of the relay, and install the top. The top should be very snug, but shouldn't be visibly bowed between the screws. The black box is now ready for installation in the car. Installing the Black Boxes ========================================================================== Installing the Black Boxes Installing the black box. The headlight assembly has been removed Now install the black boxes in the car close to each headlight. First decide on a good mounting location. If you unscrew your parking lights you will notice a lot of unused available space behind them. I mounted mine well forward of the headlights, right behind the parking lights. This makes installation more tricky, but the final product will be less visible. Be sure that the wiring and connections will not interfere with the headlights, (including the plastic shrouds behind them,) with the actuator mechanism in either the up or down position. Also have a plan for tying down the connectors with the black box NOT installed. But first about the orientation of the boxes: The boxes should be mounted such that the relay movement is not vertical. If it is mounted in this direction, each bump encountered will simulate the relay being energized/de-energized causing the headlight(s) to cycle up and down. As long as the box is built as directed the only way this can happen is if the box is installed with the 1" X 3" sides mounted horizontally. Avoid that position. Make sure that wherever you locate the black boxes, all connections will reach, and no parts will interfere with proper headlight operation. Before testing the system, temporarily install the black boxes with foam tape. After the system is fully tested and operational, the black boxes can be easily removed and additional adhesive can be added to both sides of the foam tape for a more permanent installation (I used Permatex brand Super Weather-strip Adhesive but I hear that 3M brand also works well.) Be sure to clean all surfaces prior to installation, and follow the instructions on the tube Raise the headlights and de-energize the circuit. Remove the headlight bezel (the plastic shroud around the headlights, held on by 4 screws) for better access. Install the black boxes as desired. Splicing in the Connectors ========================================================================== Splicing in the Connectors The new connectors are at the right, connected directly without the black box in between to maintain factory wiring. In this step you will cut through your headlight actuator wiring and splice in two matching connectors. After this step is completed you should be able to plug the spliced-in new connectors together and restore stock headlight operation. The entire process will probably take about 1 to 3 hours per side. I recommend that you only work on 1 side at a time. Preparation -------------------------------------------------------------------------- De-energize the circuit. Verify the circuit is de-energized by placing the dash switch in the "down" position and turning the headlights on. If the headlights are on (they can be on in the up or down positions) or the actuators move, the system is *not* de-energized! *Do not* proceed. To increase access, remove the headlight bezel (plastic shroud) from the headlight by removing four screws. Next locate the actuator engine: it is right below the manual actuator knob. Having located the actuator engine and its wiring, detach its wiring connector from its support by pushing it downwards. Take the connector apart by pressing in the retaining clip on the side and pulling. (On earlier Miatas, the upper part is also attached to the frame with two clips; reach behind it and push them together.) Remove the electrical tape, and plastic cover from the body side (female connector) wiring for a length of about 8 inches. (See below for the color of the wires to cut.) Select the easiest spot in this wiring to cut the wires. Since you will be stripping these ends and soldering to them within the confines of the engine bay, (or crimping on connectors, if you must), you probably want to cut relatively close, but not too close, to the connector. Check that the fuses are removed and cut the following 5 wires: -------------------------------------------------------- |1993 & before ||1994 & after | -------------------------------------------------------- |Black ||Black | -------------------------------------------------------- |Brown ||Brown | -------------------------------------------------------- |White w/ Red stripe ||Red w/ Green stripe | -------------------------------------------------------- |Green w/ Blue stripe||Green w/ Blue stripe| -------------------------------------------------------- |Red w/ Yellow stripe||Red w/ Yellow stripe| Perform a best guess as to the lengths of your desired wiring paths from the actuator connector and chassis harness to where you want the extra connectors to be located. Disconnect the actuator connector. This should now come free from the car. The first half of the new connector -------------------------------------------------------------------------- Take the actuator connector to a suitable work space. Select the half of the new connector that has 5 pins and one hole. Set the other one (1 pin and 5 holes) aside. It will be installed on the car in the next part. Cut the wires on the new connector about 1" longer than the desired length determined in part one. Select the colors to be spliced together as follows: -------------------------------------------------------- |1993 & before| |New Connector||1994 & after| -------------------------------------------------------- |Black ||Yellow ||Black | -------------------------------------------------------- |Brown ||Brown ||Brown | -------------------------------------------------------- |White w/ Red ||Blue ||Red w/ Green | -------------------------------------------------------- |Green w/ Blue||Green ||Green w/ Blue | -------------------------------------------------------- |Red w/ Yellow||Red ||Red w/ Yellow | Note that in this assembly the white wire on the new connector is not used. Cut it about 1-2" from the connector body. Splice each wire on the new connector (5 male 1 female) to the actuator connector as described in the soldering section, using the colors listed above. (If you use crimp-on butt connectors, at least check that the connections are secure, and wrap the entire bundle very securely with electrical tape to take stress off the connections.) The second half of the new connector -------------------------------------------------------------------------- Out at the car, perform the above operations in the same way, with the following differences: Use the 5 holes and 1 pin portion of the connector. This way you can connect the two new connectors and everything should function normally. Don't cut or strip the white wire. This will be your connection to the left/right switch. Make sure you use the lengths determined in part 1 for the length of this connector (+1".) Checking it so far -------------------------------------------------------------------------- Check for any exposed wiring/solder connections up to the new connectors. If you've melted any shrink tubing or electrical tape, re-tape it to prevent shorts. If there are any pointy spots on any wire, remove the tape or shrink tubing, grind them smooth with sandpaper or a file, then re-tape them. This is the only real change to the car, and the only one you can't fix by removing the black box. Make sure it's right. Make sure that the dashboard switch is in the "up" position. Verify that the fuses are removed, then connect the two new connectors and the factory actuator connectors. Re-install the headlight bezel with the 4 screws if removed. Make sure that all parts have ample free space and all wiring stays clear from the moving headlights, (including the bezels) and the actuator mechanism. Twist ties (garbage bag) could work for a temporary fix. Cycle the actuators down and up (by rotating the manual knob in the indicated direction only) and ensure there is no interference. Now carefully re-energize the circuit by re-installing the fuses. (And reconnect the wiper motor connector if you took it off earlier.) Nothing should happen other than a click from the retractor relay telling the actuators that they should be up. Cycle the actuators using the dash switch, and by turning the headlights on and off. All circuits should operate as before. If everything works as it should, proceed with the other side. Don't forget to pull the fuses again before proceeding. Installing the Switch ========================================================================== Installing the Switch Determine a suitable location for the switch. It should be easily accessible for the "Quick Wink", but not in the way (to be bumped by legs or when reaching for the lighter.) The switch listed doesn't fit in the cutouts in the dash very well. Before cutting or drilling for the installation of the switch, be *certain* there's ample room behind the panel for the switch wiring! Most of the dashboard and front center console has metal behind it. (Incidentally, the section on radio removal on miata.net may be helpful in removing the console.) I located mine on the small panel between the cup-holders and console storage area. Another possible location would be just forward and below the button on the brake handle. This position seems like a natural position for the right hand, but may interfere with your audio system. Suggested switch locations. Note that location 2 may not be visible when driving due to the hand brake handle. Leon van Dommelen's location for the switch. Needs a lot of cutting and filing to get it in there, though. If the listed switch is used, simply drill a 15/32" hole and install the switch. Because I used a snap-in rectangular rocker switch I was forced to cut a rectangular opening. Using a sharp knife, slowly enlarging the drilled pilot hole, I ended up with a neat hole that the switch snapped securely into. Take your time, this will be the only visible part of the system (without detailed inspection.) Next find a suitable ground connection. Because my switch is in the center console, I chose to use a bolt on the rubber shift lever boot. (A ring-type, instead of spade, connector is ideal for this bolt.) Don't try to tie into the ashtray light, neither of these wires are a true ground. Under the dash there are also many good grounds, look for a bolt you can loosen, slip a spade type connector under, then re-tighten. Install the ground wire to the ground by soldering the spade connector onto one end of a wire. Run the wire to the switch, cut it to the proper length, and install a female quick disconnect. Install this quick disconnect to the number 2 terminal of the listed switch or the center terminal of a one pole switch. Next you have to run a wire from each of the headlights to the switch. I was surprised to find that this was the most difficult part of the project for me. First I de-energized the circuit. Then I started by carefully cutting the existing tape away from the soft gray boot on the firewall that the existing wiring harness uses. Removing the relay cover provided some extra working space, but the clutch hydraulic line is just plain in the way. After exposing the end of the boot, the control wires can be pushed gently through the boot, and retrieved at the interior of the car. It may take a few tries to locate the wires. Gently pull them through. The location I used is indicated in the picture as 1. Another possible way to duct wires out of the engine compartment into the passenger compartment is to use the rubber grommet slightly to the right of the steering wheel position. The grommet comes off the firewall by squeezing it in the right place. You can cut a slit in the rubber to pass the wires through without noticeable effect on its water resistance. This is indicated as location 2. I will assume you use location 1. I then ran the wires in the engine compartment through all the tie downs the existing harness uses, and used tie wraps to hold them in place where there were no existing tie downs. Make sure the wires are not run across any sharp metal edges or engine components that will get hot. Check to be sure they will not get pinched when closing the hood. Solder the ends of the wires to the white wires on the chassis connectors and tape up these solder joints. Pull any slack out of the wires, moving toward the interior of the car, tightening the tie wraps as you go. Gently pull the remaining slack into passenger compartment. In the future, I may move these wires into the existing plastic conduit, but after trying to get the tape off the gray boot, I'm somewhat reluctant. Because my switch is located on the right side of the driver, I then ran the existing length over the frames for the clutch pedal and steering column, right along the top of the dash. Be sure to feel for sharp metal edges before deciding on the path you choose, there are plenty of them. It would be much simpler to run the wires along the lower edge of the dash, or tie wrapping it to existing harnesses, but I didn't want it to be in the way when removing the panel below the steering column. Run the wires all the way up to the switch, cut them to the proper length, and install a female quick disconnect on the end of each. These are useful in the event that the wires are installed backwards (i.e. switch to the left, right headlight goes up) they can simply be swapped. Install these on the 1 and 3 terminals of the listed switch, or on the two outside terminals of a one pole switch. Re-energize and test the circuit. Final Connection ========================================================================== Final Connection Before electrically connecting the black boxes, double check that the fuses are removed, and the dash switch is in the up position. Detach the new connectors from each other and to the corresponding black box connectors. With the fuses removed, cycle the headlight down and up with the manual knob (under the "turn clock-wise" cap) only in the clockwise direction. Check for any interference. Re-install the headlight bezel and check again. Install the cap over the manual knob, check that the dash switch is up, and re-install the fuses. A click should be heard from the actuator relay (near the air intake.) Now check the system: * Lower the headlights with the dash switch. * Turn the headlights on. Verify they are both lit. Turn the headlights off. The actuators should operate normally for all the checks above. Try the switch. If the operation is reversed, swap the wires on the 1 and 3 (outside) terminals of the switch. Check that the wiper motor connector is reconnected, in case you disconnected it earlier. Congratulations. Your car has just joined that elite group of winking Miatas!