Headlight Wiring Harness
12-16-2002, 08:51 PM
#1
Racer
Thread Starter
Headlight Wiring Harness
Well, I purchased a wiring harness/relay kit from SUVLIGHTS, along with their Sylvania Silver bulbs for my new H4s.
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The harness kit appears almost complete - I'll post a picture tomorrow (the camera is in the office) but the main elements include:
Wire bundle, about 5 feet long, inside of plastic tubing, keeping it all nice and neat with tie offs.
At one end, headlight socket that fits the H4 bulb, and a 6 inch ground wire with ring lug for attaching to a screw or bolt on frame.
At the other extreme end, same set up, for the other headlamp. PLUS, wired into the bundle, a male headlight plug (substituting for the headlight bulb spades) for the plug/wire that normally goes to the H5 headlight bulb.
This male plug is wired into two 30 amp relays, presumably one for high beam and one for low beam. Other wires coming to/from the relays: the two afforemention wire bundles going to each headlight, and two wires, with ring lugs, going to the battery.
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The entire set up is neat and tidy and appears well constructed.
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No instructions come with it.
But, in theory, low wattage runs from the headlight switch, thru the existing lines, to the fuse box, to the relays, via the male lamp plug on the harness. Since there is only one male lamp plug, I would guess only the existing fuses for the left hi and left low beam are necessary. When the low wattage "low beam on" current reaches the relay, it energizes both the right and left low beams with current directly from the battery. Ditto the "high beam on" low wattage current coming from the swithch, thru the fuse, thru the female plug to the relay.
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Given the quirkyness of all the 964 sensors, does anyone see a problem with only the left hi and low fuses supplying power to the relay?
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Appears the only required mod will be an adaptor for the harness male light plug and the existing plug that normall plugs into the H5 lamp. Otherwise, unless I am really missing something, this should work fine.
Whatcha think? (or has my description defied all comprehension?)
Chuck
93 C2
-
The harness kit appears almost complete - I'll post a picture tomorrow (the camera is in the office) but the main elements include:
Wire bundle, about 5 feet long, inside of plastic tubing, keeping it all nice and neat with tie offs.
At one end, headlight socket that fits the H4 bulb, and a 6 inch ground wire with ring lug for attaching to a screw or bolt on frame.
At the other extreme end, same set up, for the other headlamp. PLUS, wired into the bundle, a male headlight plug (substituting for the headlight bulb spades) for the plug/wire that normally goes to the H5 headlight bulb.
This male plug is wired into two 30 amp relays, presumably one for high beam and one for low beam. Other wires coming to/from the relays: the two afforemention wire bundles going to each headlight, and two wires, with ring lugs, going to the battery.
-
The entire set up is neat and tidy and appears well constructed.
-
No instructions come with it.
But, in theory, low wattage runs from the headlight switch, thru the existing lines, to the fuse box, to the relays, via the male lamp plug on the harness. Since there is only one male lamp plug, I would guess only the existing fuses for the left hi and left low beam are necessary. When the low wattage "low beam on" current reaches the relay, it energizes both the right and left low beams with current directly from the battery. Ditto the "high beam on" low wattage current coming from the swithch, thru the fuse, thru the female plug to the relay.
-
Given the quirkyness of all the 964 sensors, does anyone see a problem with only the left hi and low fuses supplying power to the relay?
-
Appears the only required mod will be an adaptor for the harness male light plug and the existing plug that normall plugs into the H5 lamp. Otherwise, unless I am really missing something, this should work fine.
Whatcha think? (or has my description defied all comprehension?)
Chuck
93 C2
12-17-2002, 03:30 PM
#2
IHI KING!
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The harness sounds complete. When I installed a relay harness in my car back in '93, I had to cut off the H4 connectors and run extension wiring from the trunk to the headlight buckets. I felt that was easier than removing the fender liners, rubber grommets etc. After cutting off the connectors, I ran heavy guage wires thru the normal wiring tubes and then soldered and shrinkwraped the connectors back on.
I've had no problems with the installation and I run 80/100 watt bulbs. I'm sure it can be done in other ways. The key is having the high-current relays in place to take the load off the light switch.
I've had no problems with the installation and I run 80/100 watt bulbs. I'm sure it can be done in other ways. The key is having the high-current relays in place to take the load off the light switch.
