gtstcactus

A few weeks back when I changed my battery & terminals...

I cut the old terminals off and found I was a little short on length, got some more wire and soldered it to the main wire to get the length right so I could connect the terminal to the battery....

Got the car running, DOME fuse was fine as I used the power mirror folding function....

Drive across town, wonder what the button next to the other mirror controls did so I pressed it - discovered it was the sonic mirror cleaner / heater button. I then notice the mirrors no longer fold in...

Took me a while to work out what the problem was as the mirrors also lost the adjustment function - that is on a different fuse tho.

A week ago I was checking all the fuses and discovered the "Dome fuse" under the hood was blown - its a 20amp fuse. I replaced it, and everything seemed fine again.... Yesterday I notice the mirrors stopped folding again, so I replace the fuse and all is well again.... Worked all day!

Anyway out this morning and what do you know.... no internal lights or mirror folding - the dome fuse again!

So can anyone help me with this??

Is there something obvious I should be looking for?? How does one diagnose this problem???
Do I need to get a multimeter??

I'd stick a bigger fuse in but I've seen what can happen when someone does that and I don't really want a fire in the car!!!!!!!

I suppose I can just keep replacing the fuse, but it's really just a band aid fix, I'd prefer to get to the route of the problem and sort that out...

PuReChaos

The reason for a fuse to blow is because there is excess current draw in the circuit or there is a short to ground before the load.

This could potentially bit a bit tricky to diagnose as the dome fuse powers multiple different circuits. For the 92 ES, it seems that the 20A Dome fuse powers: Radio, cassette tape player, compact disc player, power antenna, interior light, personal lights, door courtesy lights, ignition switch light, trunk room light, electronic moon roof system, instrument panel lights, door lock and theft deterrent system, locking with wireless remote control system. And I guess in your case it also powers the folding mirrors which as far as I can tell weren't offered in the US. If there was any work done on any of those circuits it could be that it wasn't properly done and results in a short.

But honestly, for as many circuits that rely on the Dome fuse, I wouldn't be surprised if 20A wasn't enough to support many of these circuits operating at once. This is probably why in the 3ES they added more fuses to support individual circuits. Even with that said, I wouldn't suggest putting a higher amperage fuse in there.

If you truly want to diagnose this then yes, you will need a multimeter and to take the time walk through each circuit that relies on the Dome fuse. As well you could possibly list some more information, such as what of the listed system are you using when the fuse blows out. Does the fuse blow immediately as you replace it... and so on.

I'm still not sold on the mirrors being stock and those potentially being the cause of your blown Dome fuse, especially after you stated:

gtstcactus

The mirrors are a stock option. They are stock / factory for the JDM market which is where most of New Zealands cars come from.

I can't seem to establish a link between the fuse blowing and me doing something....

I replaced the fuse a couple of days ago and it was fine, I used the folding mirrors I used the interior lights, all seemed fine. This morning I was out driving and noticed the interior lights weren't working and thought to myself it's the dome fuse AGAIN... So I'm really struggling with a cause.

As for me pressing the sonic mirror button the 1st time the problem occured, I really don't know it was the cause, I noticed the fuse being blown 30mins after we'd soldered some more wire onto one of the battery cables so the terminal could reach the battery post. It was not blown immediately after we did that, but I noticed it was blown after using the sonic mirror button. It may have blown on the trip home for all I know....

I don't have a power antenna, I think it might be integrated into the rear windscreen. I don't currently have a stereo connected as that last owner made a mess of it, so I put the new head unit he got in the glove box. The wires from the stereo are all sitting in the void left by me removing it. I don't have a moon roof / sun roof. I don't have the theft deterrent system. I have the remote control locking turned off until I can get a button for my remote key, and work out the right size battery for it also. No CD player / stacker in the boot either.

Upon replacing the fuse it seems all good.... I test the various functions out all seem to work fine, and then I'll go to switch a light on or open the door and notice the lights aren't working so the fuse has gone again... Not real helpful I know but that's the way it is...

gtstcactus

I replaced the fuse last night, didn't drive anywhere, the only thing I recall doing was pressing the trunk release lock / unlock button in the glovebox... I noticed this morning the fuse was blown... Perhaps the main interior light made it blow, or maybe it was the button.... I replaced it again this morning, it blew within 5 minutes, I didn't do anything apart from start the car and drive...
I'm wondering (tho I believe it's on a different circuit/fuse) if the missing cig lighter is the cause.. the 2 wires that connect the lighter are just poking out the hole where the lighter was, the copper wire ends are exposed to the world not insulated with tape or anything, I'm wondering if the wires touching the metal ashtray surrounds is causing the short... Not exactly scientific just thinking possibilities...

I'm not even sure how to diagnose the short with the multimeter.... Scotty Kilmer showed a handy device in one of his Youtube videos I think it was called the ECT2000 or something like that, basically you plug one part into the offending fuse socket, and then turn the other part on and it beeps as you get closer or further away from the problem (think hot & cold game, lol)... Seemed like a speedy way to find an electrical problem, I bet it's not cheap but a damn handy diagnostic tool!

I might try wiring up the replacement lighter I've got and see if that helps....

The only common occurrence I'm aware of in this fuse blowing is driving..... and that sure isn't a lot of help!

gtstcactus

Ok the Dome fuse is responsible for interior lighting..... amongst other things..

For some reason the previous owner removed the trunk light from the car... The light and fitting were just gone, with the 2 wires hanging out the hole loose with open ends.... Could this be the cause of my short???? It's on the right fuse...??? The 2 wires can quite easily touch each other, or the metal surrounds of the body...

Last visit to pick a part I grabbed the light & connector / plug out of a ES300 being wrecked.... So I just wired the light up and it's going fine.... I mucked around for a little bit, sorted a couple of other little things and the fuse hadn't blown 10 minutes later, I haven't been for a drive yet too see if it blows while on the road, but I'm hoping that the 2 naked light wires were the culprits, and the problem is now solved!! Fingers crossed!

PuReChaos

Yes the power line touching the body would cause a short which would blow the fuse. I would just tape any loose wires with electrical tape to say the least.

gtstcactus

Yeah I wired it up crimping bullet connectors to join wires, and electrical tape to cover up any open copper wiring... Been for a drive to get Pizza and still hasn't blown!