Sedan Headlights on P5

[KrayzieFox]

Has anyone done this? I wanna swap headlights between the P5 and MP3 and I know it's easy to put P5 headlights on the sedans, but how about the other way around?

 

[reut1]

Has anyone done this? I wanna swap headlights between the P5 and MP3 and I know it's easy to put P5 headlights on the sedans, but how about the other way around?

mattv just did a retrofit of sedan lights on his p5 and he didnt mention anything about fitment as far as i know

 

[KrayzieFox]

I know the fitment isn't an issue, but I'm curious about the wiring. I'll shoot him a PM. Thanks.

 

[BlackCherry]

I've also been curious on this, no one's been able to give me a solid answer though

 

[ForceFed]

It's just wiring, nit sure why you guys are making it harder than it has to be. It's simple circuitry that will need to be traced and changed, nothing more to it. HMO have told both of you the hardest part will be sourcing the plugs for the swap, but no one thinks it's that simple when it is. Get the lights, the plugs, and your DVOM and get to work. At most I heard the P5 uses negative triggers for the lights which might require the use of a couple basic relays. Something else that is fairly simple and not rocket science.

 

[justanothermp5]

get h4 hids, wiring problem solved

 

[ForceFed]

That is one option, but you stillbhave to figure out the wiring.

 

[KrayzieFox]

Normally I'd be out there trying to figure it out on my own, but wiring isn't my strong point at all. I have both cars in my driveway, an MP3 and a P5.. so the harness, plugs, wires, etc. are all there. I don't need to source any parts. I would just like to know if someone else has done the wiring already so that I don't have to screw s*** up cuz I dunno what I'm doing. Mechanical stuff I'm ok with, but wiring is not something I have enough experience with.

 

[ForceFed]

It doesn't get much simpler oneiringbthan this swap IMO. If you can wire up a radio, you should be able to figure this out. The easiest solution is to go to HID's hands down.

 

[dandan2]

headlights are the most easy wiring there is. all u have to do is figure out wich one is the high beam. the ground is obvious. its really not that hard. go buy a test light connect it to a ground turn the lights on and have someone trigger the brights and figure out wich of the 2 wires are the brights.

 

[KrayzieFox]

I think I found what I was looking for.

But what's the relay for?

 

[ForceFed]

The relay is triggered and powered by the high beam which then switches from the N/O terminal 87 and changes it state to a closed contact which then powers the high beam filament and turns off the low beam filament by making 87a an open contact.
As long as the P5 runs both highs and lows when the high beams are engaged then this will work.

 

[Matt V]

get h4 hids, wiring problem solved

While that's the easy answer, the complicated answer is much less simple than that.

YES, you can use an H4 HID kit however, this will only solve the low beam issue. You will have a driving light but once you need high beams, you're screwed. Basically you have to make a harness that goes from the factory H7 and 9005 connectors to a shared H4 plug.

 

[KrayzieFox]

So would this work?

Cut the wires going to the plug on the sedan and simply splice the three wires (positive low, positive high, and shared ground) into the P5 harness and be done.

Seems too simple to work..

 

[ForceFed]

No, you have to use the relay because the P5 uses negative switching and the sedan dies not. This is why they used the relay. Follow that diagram and it will fix you right up.

 

[KrayzieFox]

No, you have to use the relay because the P5 uses negative switching and the sedan dies not. This is why they used the relay. Follow that diagram and it will fix you right up.

I dunno what that means, but I'll take your advice. Thanks

 

[ForceFed]

If you look at the relay and the way they run the wires..you will see they dont use a + where it should be...THey have the wiring reversed going into the plug ad the switching Element from the Relay is actually a switching ground.


Not sure why they did it this way, but there must be a reason.
Let me study the diagram a bit more and see if it can be swapped.

 

[KrayzieFox]

Sure, sounds good. I'll try cut down on your efforts a bit. Here are the diagrams

Sedan
P5

 

[Matt V]

Use the diagram from the first page, that looks good to me.

 

[KrayzieFox]

Alright, I got the P5 taken care of.. so how does one go about hooking up P5 lights on a sedan now? I'm just swapping from one to the other.