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I never bothered to do a writeup of how I installed my HID R Bi-Xenon retrofitted lights onto my halogen equipped car since it was such an oddball case and didn't think there would be anyone else that would run into the same issue. Well, another member ran into probably the same problem, so I posted more about it, and thought it would be good to copy it here for record keeping.
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I dug up this old wiring diagrams I made. This is the plug on the car side. This plug connects to the intermediate headlight harness, that I purchased to cut up. Volvo P/N 30678832. Check your wiring colors and it would be best to check the actual pin outputs with a volt meter also. What I did was put the headlight switch into all of the different states (turn dial) and measured the output of each pin. This is what I wrote down almost 9 years ago when I first put the R retrofitted lamps on, but it could be wrong.
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On that harness, I cut the lead from the car side, pin 3 and wired it to the DC-DC Buck converter. Amazon doesn't sell the one I used anymore, but this one is close (also the same Drok brand I used) DC-DC Stabilizer 9v-36v to 12V
The output of the buck converter, I measured to make sure it was a stable 12V when the headlights are supposed to be on. I then wired everything to an auxiliary fuse box (this is the exact one I used) 12-Slot Relay/Fuse Box and got some normal Bosch style 5 pin relays. I used these: 10pk Bosch Style 5-pin 12V Relay SPDT
Then the output the relay gets routed back to the headlight 'input' low beams.
I used all 5 slots of the relay box for:
1. Left Low Beam (car side pigtail, pin 3 left side)
2. Right Low Beam (car side pigtail, pin 3 right side)
3. Left High Beam (car side pigtail, pin 7 left side)
4. Right High Beam (car side pigtail, pin 7 right side)
5. DRLs (R Lamps) (car side pigtail - one of the sides, pin 2)
I then wired the +12V feed for the aux fuse box to the main power feed right next to the driver side front strut tower, and found a ground also close to there. I don't remember what sized wire I used, but I calculated the power draw from the headlights at max power, and used the distance. Probably 12 AWG wire.
Here's a pretty bad picture of it that shows basically everything.
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Red Circle - Where I connected to +12V
Black Circle - Close to where I connected to GND
Blue Circle - You can see the aux fuse box tied down to the other hoses and wires
Green Circles - The headlight intermediate harnesses are here
Red Line - Running the line from one side to the other.
The whole thing is plug and play onto the Volvo S60T5 halogen wiring harness, and the R lamps. And all the wires hide very nicely under panels, along with the fuse box itself. I made a harness with heat-proof wire sheathing and shrink wrap to protect the wires. I've been using the setup for the better part of 5 years and it has been flawless.
For the prior 4ish years, I was running some really low quality relays that were so slow to act that the PWM signal actually didn't turn them off with the fast refresh rate. I got lucky here and ran them that way for a few years until one of the crap relays started sticking and not turning on, thus requiring me to do the whole voltage regulator + fuse box solution.
__
I dug up this old wiring diagrams I made. This is the plug on the car side. This plug connects to the intermediate headlight harness, that I purchased to cut up. Volvo P/N 30678832. Check your wiring colors and it would be best to check the actual pin outputs with a volt meter also. What I did was put the headlight switch into all of the different states (turn dial) and measured the output of each pin. This is what I wrote down almost 9 years ago when I first put the R retrofitted lamps on, but it could be wrong.
On that harness, I cut the lead from the car side, pin 3 and wired it to the DC-DC Buck converter. Amazon doesn't sell the one I used anymore, but this one is close (also the same Drok brand I used) DC-DC Stabilizer 9v-36v to 12V
The output of the buck converter, I measured to make sure it was a stable 12V when the headlights are supposed to be on. I then wired everything to an auxiliary fuse box (this is the exact one I used) 12-Slot Relay/Fuse Box and got some normal Bosch style 5 pin relays. I used these: 10pk Bosch Style 5-pin 12V Relay SPDT
Then the output the relay gets routed back to the headlight 'input' low beams.
I used all 5 slots of the relay box for:
1. Left Low Beam (car side pigtail, pin 3 left side)
2. Right Low Beam (car side pigtail, pin 3 right side)
3. Left High Beam (car side pigtail, pin 7 left side)
4. Right High Beam (car side pigtail, pin 7 right side)
5. DRLs (R Lamps) (car side pigtail - one of the sides, pin 2)
I then wired the +12V feed for the aux fuse box to the main power feed right next to the driver side front strut tower, and found a ground also close to there. I don't remember what sized wire I used, but I calculated the power draw from the headlights at max power, and used the distance. Probably 12 AWG wire.
Here's a pretty bad picture of it that shows basically everything.
Red Circle - Where I connected to +12V
Black Circle - Close to where I connected to GND
Blue Circle - You can see the aux fuse box tied down to the other hoses and wires
Green Circles - The headlight intermediate harnesses are here
Red Line - Running the line from one side to the other.
The whole thing is plug and play onto the Volvo S60T5 halogen wiring harness, and the R lamps. And all the wires hide very nicely under panels, along with the fuse box itself. I made a harness with heat-proof wire sheathing and shrink wrap to protect the wires. I've been using the setup for the better part of 5 years and it has been flawless.
For the prior 4ish years, I was running some really low quality relays that were so slow to act that the PWM signal actually didn't turn them off with the fast refresh rate. I got lucky here and ran them that way for a few years until one of the crap relays started sticking and not turning on, thus requiring me to do the whole voltage regulator + fuse box solution.
