Look what Santa brought me this year…..LED headlights…..how did he know that’s what I wanted?
The stock headlights on the North American XJ12C are dim 5 3/4″ sealed beams rated at 37.5/50 W. Shortly after buying the car, I replaced the sealed beams with 5 3/4″ H4 headlight housings and the strongest H4 bulb I could find rated at 90/130 W. The difference was incredible and at first I was worried about blinding oncoming traffic, but I have not been flashed in over 15 years of running these headlights.
These headlights are wired directly from the battery through high gauge wires and relays to each headlight. I have also upgraded the original glass fuses with modern blade fuses.
Over the years I have added more loads to the electrical system such as a high volume electric radiator cooling fan and a couple of amps for the sound system. I have updated the 70 amp Motorola alternator with a 94 amp GM unit and John’s Cars adapter bracket. Even the updated alternator has trouble keeping up with the cooling fans and headlights when idling in drive.
I started getting interested in LED headlights a couple of years ago as they promised more light using a lot less amps. The technology just didn’t seem ready until recently. The bulb manufacturers are taking more effort to shield the LED’s in a similar way to standard halogen H4 bulbs, which should control light scatter and blinding of oncoming traffic. The reason I selected the bulbs below is that they:
- have shielding of the LED’s
- no cooling fans to fail
- low watts (25W)
- pretty compact
- and have a sturdy looking build
They look much brighter and whiter than the halogen bulbs.
The XJ12C has four headlights. I only use the outers for low and high beam and have no use for the inner two. The dash headlight switch has a fourth position for “Fog” that is unusable unless you remove the switch surround and remove the c-clip so that the switch can be pushed in and then rotated to the Fog position. The car is pre-wired for fog lights, so I used these wires to fire a relay that controls the inner headlight locations. For these I used another pair of H4 housings and Osram Fog Breaker bulbs.
I won’t be able to test out the new LEDs until winter breaks and I can get back out on the road in a few months. I am a bit concerned about the scattered light at the top right, so will need to see how they look when you drive up to the car. Will provide an update in the spring…….
Update: It’s May and there was no spring this year….we went right to summer. After driving at night, it is clear that the left headlight is throwing too much light upwards, so I re-aligned that headlight.
