Defroster relay

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Also anything dealing with the elctrical system.
FiReSTaRT
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Defroster relay

Post by FiReSTaRT »

I have 2 questions on this topic:

1) Where do I locate it? (I know it's somewhere underneath the dash of my 95RS but there are several relays down there, so I don't know which one it is)

2) Do I have to buy it at the dealership for $30 or is there a place in the GTA where I can buy it for a more reasonable price? Relays are only supposed to be like $3-5 a pop. I live in the west end.
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Grants
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Post by Grants »

You sure thats the problem?

If so the wire colours going to it are:
BLACK / YELLOW
YELLOW
BLACK / BLUE
BLUE

Hope that helps and your right, its one of those relays under the dash. Hopefully those wire colours will help.

Any 12 volt relay will do - you don't need to go Mazda. Just make sure you go for a high current rating, its on a 40 amp fuse but I don't know what current it will draw but I'd recommend matching the fuse size at least.
“You’ll find, that the only thing you can do easily is be wrong, and that’s hardly worth the effort.”
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acespdz
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relay

Post by acespdz »

Is this for the rear defrost. Well if it is its under the dash on top of where your would put your left foot when relaxing. the colours are as the previous post. i put in a universal relay from CT and it works fine. my orignal was all rotted and breaking apart. anyways hope this helps. mine works fine i just dont have a lite on my defrost button i have to take apart the dash to change the LED dont have the time right now. happy hunting :pimp:
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Post by FiReSTaRT »

Thank you gentlemen. I'll take a look at it this evening. I don't care about the LED either, as long as I can see what's behind me.
I'm not 100% sure about the relay... I already replaced the defog fuse, so all I have to do is replace the meter fuse. If it doesn't work, then I'll know it's the relay and replace it.

First rule of troubleshooting: Always try the cheap solution first ;)
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FiReSTaRT
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Post by FiReSTaRT »

Ok, I'm going ballistic. CT doesn't have any 4-prong relays in stock and they can't even order them. Same with Partsource. Napa might be able to order one from a supplier, but who knows how much it would cost. In any case both the relay and the harness look like they were dipped in some nasty tree-sap, so I'm assuming it's gone and I'll need to replace both.

Do you guys have any other ideas for southern Etobicoke or south-western Mississauga?
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Grants
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Post by Grants »

You should be able to get one almost anywhere....

Do the wires going to the relay all go into one plug and your having trouble getting one with the right pin cofigeration? You can always get any relay, cut the plug off and install spade terminals.
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Post by FiReSTaRT »

I don't know how I'd convert to a 3-prong or 5-prong. Nobody has a 4-prong 40A relay. I'm in touch with one of the mx-3.com members who's parting out a car, so I may be able to pull his, including the harness (since mine is as gone as the relay). That would be the ideal solution. If you can give me some tips on converting it to a 5-prong, I'd be willing to listen, since I KNOW I can get one of those at CT, and I can always save that as a last-resort option.

edit: I'm not an electrical guru, but I can do a neat splice, as long as you tell me which wire goes where. My experience is mostly with color-coded deck installs and replacing damaged wiring in the charging/cooling systems.
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Grants
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Post by Grants »

I'd need to check but aren't 5 prong the same as 4 prong with 2 of the prongs being doubled up?

Easy to tell you which wires go where if you can confirm the wire colours are right as mentioned previously.
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Post by Grants »

The connections are:

Positive power wire (BLUE) to terminal number 30

Switched (power) wire (BLK / BLU) to terminal number 87

Positive control wire (BLK / YEL) to terminal number 85

Switched (control) ground wire (YELLOW) to relay coil terminal 86
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FiReSTaRT
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Post by FiReSTaRT »

Thanks for theinfo m8... And how would I know which terminal is which on a 5-prong relay?
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Grants
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Post by Grants »

The terminals will (should) be numbered and the extra prong should be 87A which has continuity with terminal 30. So just don't use that one (or use it and don't use terminal 30 - same thing).
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FiReSTaRT
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Post by FiReSTaRT »

Actually after taking a better look at the relay, I realized it was 20A. A replaceement may be easier to find. Still, if I can replace the relay/harness with stock components, I'll be a happy man :)
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Grants
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Post by Grants »

Seems odd to have a 20A relay on a 40A fuse... wonder what Mazda were thinking?
“You’ll find, that the only thing you can do easily is be wrong, and that’s hardly worth the effort.”
FiReSTaRT
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Post by FiReSTaRT »

It was probably designed by the same guy who put a separator into a gasoline fuel system. When I showed it to my mechanic, he was still saying "Wtf?!"
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acespdz
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custom hardnes

Post by acespdz »

I had to replace my relay and wiring but all i did for the wiring is connect the wires with plugs like the ones for speakers and connected it to a relay i got from CT in my area. it works great. Try that out or if you still cant find a relay and are near Queensway check out a place near islington and queensway. i'm not sure the name of the place... Good luck :pimp:
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