Cane

I ordered a harness and after reading a bunch online, it seems relays are mostly cheap chinese ones that should be upgraded. the harness comes with these two relays : https://i.imgur.com/YRI1ILQ.jpg

I found some hella relays rated at 20/40A. being the noob that I am electricity-wise, I have no idea if it'll work or not. Here is what I was thinking of getting :

so would this replacement work or I need to look for something else?

thanks

SteveMongr

They look a little different. Amazon ones are 5-blade connector. One of yours appear to be 4-blade, the other 5-blade
The numbers on top of relay describe that connections function. I would think they need to be matched.

aj2494

That relay will technically work, but you wouldn't be able to plug it into the harness. Steve is right, if you want to directly plug it into the harness, you need the same relay. Also, is this the Putco harness? If so, be ready for everything to fall apart on you.

Cane

I noticed that after posting when I saw how 87a is on one but not the other.

I searched hella because that's what people recommend in the threads I read, but for an application like this is there any chance I can find a brand-name relay that has the same layout as those? After searching the numbers, I keep finding these 'made in china' ones that I'm sure are the same as the ones in the kit.

example:
It's not a putco, I read bad things about them and figured if I was to spend 30$ on it (it was even more because of currency exchange in CAD) I would rather get something that has top notch reviews. I ordered a no-name harness and I'll inspect it when it arrives. I figured if the wire gauge and overall wiring is decent, I'll replace the relays and give it a try.

Could I cut the replay plugs from the harness and splice in 2 new ones that fit with the hella/bosch/brand-name relays? Why does one need to have 5 pins instead of 4 (or vice-versa)? I get that there's a relay for low-beams and one for high-beams, but other than the intensity of the light, what differentiate one from another?

aj2494

The wire gauge isn't the issue, but rather everything else. For me, it's been the quality of the connectors and the spade terminals. It's become so bad on my Putco that I routinely have to jam my soldering iron into the terminals to melt all the plastic and then I solder whatever is loose. I've already replaced the H4 plugs since they were so unreliable. It gets very annoying because I frequently have to bang on my headlights to get them to come on.

I have no idea why those relays are different. That harness must have something different built into it, but I can't really tell you what it does without the product info and maybe a schematic. It doesn't make sense to me that it would have a closed circuit somewhere without a switch on. Personally, I would wait for it to arrive and then take a look at everything. If you're happy with it, go to NAPA and see what common relays and connectors they have, find an option that works, and splice them into the harness instead of those weird ones. Replacing the relays in my harness was a royal PITA. I ended up digging around in every Japenese car I could find at the JY for about 2 hours until I finally got what I needed. And then one died 4 months later.

Cane

alright thanks for the help and info I'll keep that in mind.

Here's a pic of the harness. I have not compared it next to the putco, but I'm guessing it's similar. 1 plug for each headlight w/ a ground, 1 plug that goes in the existing headlight connector, 2 relays, 2 wires going to the positive battery terminal and a fuse. can't find a diagram though.

aj2494

Yup, same basic design as the Putco. That one does look better though, with an actual fuse vs fusable links and the H4 plugs might be ceramic. I still don't know why you have the 5-pin relay with an 87a terminal.

at05gt

Those look like standard 5 blade relay plugs, whether the relay itself is 4 or 5 blade doesn't matter, those connectors will have 5 slots. So a 5 pin relay will work, the center plug just won't be wired to anything



There are 3 styles of that size automotive (bosch-style) relay, 4 pin (single pole single throw), 5 pin switched 87/87a (relay off supplies voltage to one leg, relay on supplies voltage to the other side), or 5 pin double 87 (both 87 legs get voltage when relay is on).

cliffy

Just install it properly and then worry about the relays, I ordered one off of eBay very similar to yours and have no issues Chinese relays and all. Just Google the specs on the relay volts, amps then make sure the pin configuration is correct. it should give.you plenty of options if you still want to change them. Make sure the relays are installed somewhere that they won't get wet too.

aj2494

They wouldn't make one relay different without a reason. If the 87a pin did nothing, they would just include two four pins. Or it could be due to the fact that this is a Chinese manufacturer and the picture is different or something. I just can't figure out for the life of me what the fifth pin would power.

at05gt

Depends on how it is wired, I have a similar harness to his and mine has a 4 pin and 5 pin relay.



4 pin relay is the power on from the headlight harness, the 5 pin relay is the switch between low and high beams.

4 pin gets its turn on signal from both low and high beams so that if there is power to the headlight circuit it is on whether low or high beams, 5 pin only gets turn on signal from high beams.

So when lows are on it triggers 4 pin relay which passes battery voltage to 5 pin relay, which powers pin 87a because the relay is off, which powers low beams.

When highs are flipped on 4 pin no longer receives signal from lows but does get signal from highs, which passes battery voltage to 5 pin relay which is now also getting high beam signal which turns it on and passes voltage to pin 87, powering the high beams.

This way there only has to be 1 power and 1 ground connection but the circuit can handle 3 operations, off, on low, and on high.

aj2494

Now that makes more sense. The only thing I don't like about that is the result if a relay fails. You'll be stuck without lights, whereas I can switch my relays if one goes bad so I always have lows.

at05gt

The picture I linked is of my exact harness and it uses standard sized bosch relays, so if one fails I can replace it. The relays in the harness he linked are the same size/style, so if they fail he can replace both with a standard 5 pin 87/87a relay and it will work exactly the same because pin 5 (87a) on relay A (4pin relay) is not wired to anything. But, you can buy both 4 and 5 pin relays at any parts store, just check the diagrams on the relays themselves and reference this:

http://www.accessconnect.com/car_relays.htm

Cane

I read everything, thanks a bunch guys. I'll wait till I receive the harness to figure out the actual setup. Relays are rated 12v/40A so I'm guessing I shouldn't go above 40A. As suggested I'll just install everything and then see what my next move is. I would probably still order some spare relays in case one (or both) fail. The purpose of this thread was basically so I could be prepared in the event I lose power to my lights while it's dark outside.

at05gt

I have a relay panel for my offroad lights and they all use the same relays as the headlights, so if something goes out I can swap a relay from my offroad lights and continue on. That being said the likelyhood of a relay failing before the fuse or wiring failing is like 1 in a million, relays are pretty stout.

Glad we could help.