You've overlooked something that I believe will be the cause of your issue. I discovered it on my 2004 only after replacing the headlights (HLs) with LEDs.
The first time that I would use the turn signal (TS), I noticed my driver's HL winking momentarily. Some time later, the driver's light would take 1-2 seconds to turn on for the first time and gradually grew to being almost every time I used the HLs.
The root cause? The power for the HLs travels up and then back down the TS stalk with no relays. The HLs are controlled with 2 separate switches inside the TS stalk. Power goes up the stalk, then goes to two distinct switches that control High and Low for each bulb, then those 4 wires come down the TS stalk and go out to the HLs. Each side inside the switch is circled in blue.
It seems that your HL switch needs some attention. As I see it, you have 2 options:
- Replace the HL switch, which likely includes the TS but I'm not sure
- Use the passenger HL power to turn relays on and off, which will then power both HLs
Myself, I would opt for #2 since I know how to do that kind of stuff. Under the hood or under the dash, it won't matter, but the easier place is under the hood.
Steps to modify stock non-relay system:
- Install 2 relays near the battery
- Install 2 15A fuses from the battery, one to terminal 30 on each relay
- Install a wire from ground to each relay, terminal #85
- Cut the LOW and HIGH beam wires but leave enough room to add wire to each end. One wire will be the PLUG, the other is the FREE wire.
- Install a wire from the Low beam FREE wire to terminal #86 on one relay, then mark that relay as LOW BEAM
- Install a wire from the High beam FREE wire to terminal #86 on the other relay, then mark that relay as HIGH BEAM
- Install a wire from terminal #87 on the LOW beam relay to the PLUG wire on the passenger's side and the LOW wire on the driver's side
- Install a wire from terminal #87 on the HIGH beam relay to the PLUG wire on the passenger's side and the HIGH wire on the driver's side
Use 12 ga. wire for steps 1 and 2, 18 ga. wire for steps 3, 5, and 6, and 16 or 14 ga. wire for steps 7 and 8.
Notice the red lines under the connections in the factory wiring below. The top one is for the High Beam indicator, the bottom two go to the Vehicle Security system. The modification above should not interfere with that since you are not cutting the wires on the driver's side.
The green lines indicate where I suggest you cut the wires for the passenger's side only.
Circuit description:
- HLs are turned on, which energizes the LOW relay
- LOW relay turns on both LOW beams
- TS stalk is moved to HIGH position, which energizes the HIGH relay and turns off the LOW relay
- HIGH relay turn on both HIGH beams
- The 2 fuses provide protected power to each relay and the HL wiring
The 2 fuses are the same size as the single stock fuse, which normally powers only 2 bulbs at a time. So with 2 fuses, if one blows out you'll at least have the other beams to drive with and not be completely dark.
As you add wires, you may want to test them as you go. This is a very basic system and there's not much that can go wrong with it.
View attachment 81108
