I ask because my headlights are only getting 8v. Lights (LED halogen replacements) are very dim and flicker. Further they go out completely on when I turn on my brights. I've traced it to HL-P (if I tap on it, they sometimes come on bright as normal). I'm going to be near a pick and pull next week and wanting to know if I can pull relays from a HID system Prius or if I need to make sure it's halogen as well. I'm wanting to replace the HL-P relay for sure and grab a spare DIM relay just in case, because the brights issue seems sus as well.
Is HL-P part of an HID system? Never heard that term? To be clear Halogen and HID are wired differently and the headlight casings are different because of how the bulb mounts so you have to replace the entire fixture. The most common job for this situation for Gen2 Prius is converting HID to Halogen fixtures and changing the wiring so you can try both halogen and least expensive LED bulbs.
I just double checked. I had the dash in the wrong place. I meant the H-LP relay. Sorry for the confusion. What I'm wanting to do is go to u-wrench salvage yard and get some replacements relays for my halogen system. I just want to make sure I don't grab an incompatible relay. The H-LP relay has a part number, so easy enough to make sure it's the same from the donor car. The DIM relay is just blue and I can't find a part number printed on it. Wanting to see if I need to make sure the donor car is also halogen or if HID relays would be okay?
If your car is originally halogen setup I would be taking the parts off of halogen car I do have both vehicles here I can go out and look in the morning but I know the wiring that comes to the bulbs from the ballasts is not the same as what's in the car for halogen lights. I would think the relays may be the same because that power just gets to the ballast for the HIDs which you don't have it'll be harder for you to find an HID car anyway most of them are going to be halogen and you have halogen now so keep everything halogen no matter what's really in the H4 sockets of your headlamps LEDs whatever as soon as the sun comes up I'll go out and check the relay pieces and see if they're basically the same part numbers but even still I would just take them out of a halogen car which is what you should be looking at at the junkyard generally speaking.
If you went from halogen to HID, your supposed to rewire - OEM wires are undersized. If you went from halogen to LEDs, you'll get a slight flicker, due to electronic noise and how the voltage was varied on the halogens for DLR. The LED circuitry will usually compensate - causing the flickering. Flickering should go away when the headlamps are in the on position NOT DLR. A rewire or resistor kit would take care of that. Hope this helps...
Thanks for checking! The issue I'm having is the junkyard doesn't have many Priuses these days. So I'll be lucky if they have any. I know the wiring is different which made me wonder if the relays where different.
The wiring is already halogen; ie: the car has H4 headlight connectors that don't have a ballast and output 12v. The issue is I live in the hicks and the closest salvage yard tends to have a very limited selection of Priuses. There's a good chance they'll only have 1 or less gen 2s. My H-LP relay has a part number printed on it so that'll be easy to check. The DIM relay which controls brights and dim is just blue, there's no part number printed on it, and when I try to look online for it, they don't specify whether it's for halogen or HID. H-LP has a part number: 90987-02025, 156700-2540. If the salvage yard only has HID Priuses then I know as long as the part numbers match then then they are the same. The DIM relay is just a blue box that doesn't have a part number. Therefore if the salvage yard only has HID Priuses the only thing I have to compare the relays is blueness.
Okay never mind I figured it out. I found this site that let's you put in your frame number which I found with Techstream. https://toyota-usa.epc-data.com/prius/nhw20/1305/electric/8401/85916U/ It looks like the relays are in fact the same. Further I now know the relay labeled DIM is also called Headlamp Relay No. 2 And I have a part number now! 90987-04010 And more important to answer my initial question for some future researcher: it's a general relay that seems to be used for a lot of things so should be interchangeable between headlight systems. It looks to be used in a lot of different Toyota owned brands like Toyota, Nissan, Scion and so fourth.
You need to hit that Toyota relay with sand paper and contact cleaner - probably the socket it fits into too. That may be the reason your getting low voltage at your lamps. Most Japanese car relays are the same, but I'm hesitant to say that, because some BMW guy will chime in and say no they're not. Then again, BMW's take special weird voltage lamps. Control the parts and your customers will become your slaves forever.. The new ones, don't even have dip sticks and if you don't pay your monthly seat heater bill - we'll disable it remotely.
Okay I sanded the relay blades and those things are fricken copper! I had no idea because all the corrosion. I end up using a helping hands to hold the relay in some CLR just deep enough for the blades to be submerged. Then I washed it off with some rubbing alcohol. Currently letting it dry. Here's hoping and thanks for the tip!
Don't know where you got the idea that Nissan was owned by Toyota, but it isn't. Nissan and Toyota are two totally separate companies.
I'm not really a car person. Mea Cupla but I appreciate the correction! Back on to the thread: The relay failed again. I'm just gonna get a junker relay. I think it's supposed to have a nickle coating, and the sand paper just kind of removed it. On the bright side it's a common relay it seems.
I think they're the same from HID and all I have both cars here they both have that 40 amp relay marked lights or something like that and they don't discern between HID and or halogen and either of the fuse boxes of either of the cars.
One thing I'm learning working on my car is Toyota seems to like to use the same parts for as many things as possible.
