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What is the HEAD fuse and the ST fuse?

Old 10-05-2013, 06:08 PM
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What is the HEAD fuse and the ST fuse?

PLEASE SEE MY LATEST POST ABOUT NEW QUESTIONS

So I made a stupid mistake today of popping my room fuse. Having replaced that, I was having trouble starting the car - everytime I turned the ignition, the car would drop dead and fritz out. So I thought, let me take out my ignition fuse and see what happens.

So I swapped the ST and the Ignition fuse (not knowing what the ST is, but hoping it wasn't important), and the car proceeded to do the same thing. Then I put the ST fuse back, and swapped the Ignition with the Head fuse. Suddenly, the car worked! After getting rid of the ABS and TC lights, the car was fine. Nothing odd.

So, I came back to look for replacement fuse that was problematic (now sitting in the HEAD slot), and I thought I'd look up what those fuses did as well. Googling, I couldn't find anything on the HEAD fuse and the ST fuse. So does anyone on this forum know? I'm guessing ST is the starter motor? But I can't figure out what the HEAD fuse is - is it the headlight fuse? But when I turned on the headlights with the faulty fuse, they worked.

In consideration, I have no idea what went wrong with that fuse. A fuse is simply a thin piece of metal that burns when overloaded. So I can't figure out why - when it is sitting in the slot for ST or Ignition, it would cause the car to drop dead and be unresponsive. Regardless, I'm going to be shopping for replacement fuses in the meantime.

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Image for what I am referring to. Any info would be great!

Last edited by JinDesu; 10-21-2013 at 07:55 PM.
Old 10-05-2013, 06:30 PM
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HEAD = Headlight Higbeams / Washer

ST = Starter

And those arent fuses, they are actually relays. Similar concept, different operation.
Old 10-05-2013, 06:38 PM
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Oh hum, relays? Single pole single throw? Maybe the relay shorted itself...

Thanks a lot!
Old 10-06-2013, 10:11 AM
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I just checked all of those on my car as well since I am also having ignition and starting problems! I just checked mine with a multimeter and they all work which is LAME I wish it was just a relay!
Old 10-08-2013, 01:13 PM
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Originally Posted by Noxity
I just checked all of those on my car as well since I am also having ignition and starting problems! I just checked mine with a multimeter and they all work which is LAME I wish it was just a relay!
Well when I put the possibly-bad-relay into the HEAD position and swapped the HEAD relay into the Ignition relay, I was able to start my car. I also was able to turn on the headlights, so I'm not entirely sure how the relay works inside and what is the problem.

Did you try swapping around relays?

Also - these relays are freaking expensive.
Old 10-08-2013, 03:29 PM
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Originally Posted by JinDesu
Well when I put the possibly-bad-relay into the HEAD position and swapped the HEAD relay into the Ignition relay, I was able to start my car. I also was able to turn on the headlights, so I'm not entirely sure how the relay works inside and what is the problem.

Did you try swapping around relays?

Also - these relays are freaking expensive.
Yes we did swap them all and test them all but unfortunately for me, that didn't work. That was actually the very first thing I tried when I got stranded. =p
Old 10-21-2013, 07:54 PM
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Well I found half my problems! The problem where when I crank the engine and everything blinks off and flickers crazily was my battery - the battery had enough power to turn the car to ACC, but upon cranking it would drop voltage and everything would disappear for a few seconds. Replacing my battery has solved that issue.

My next issue is that my radiator fans wouldn't work for some reason. After much tinkering, I found that my "CIRCUIT" relay was very hot. After pulling the "CIRCUIT" relay and turning on the car, I found my radiator fans working. Humorously, I didn't know that the "CIRCUIT" relay is associated with fuel or something, because my engine proceeded to sputter out right after.

So my question now is:
What is the "CIRCUIT" relay? I know that the one next to it is the "FUEL" relay which I assume is the fuel pump, but what is "CIRCUIT"? Looking online, it must be associated to the fuel system because people say you need to pull it when de-flooding.

I don't know why my "CIRCUIT" relay is hot, and I don't know why it affected my fans. I'm thinking to swap another relay into the position to test if it's the relay - or if something downstream of the relay is causing an issue. The only matching relays are the FUEL, EGI, and ETV. Since EGI is the gas injection relay, and FUEL is the fuel pump (assuming), that only leaves the ETV. Can someone let me know what the ETV relay is?

I'll be buying a set of relays to replace my CIRCUIT relay, but I want to see if there's a short term solution for me to confirm the issue.
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