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Accessories Resetting

govich

By govich,
in Car Audio & Electrical

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govich Community Regular

govich

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Hi guys, i installed a new head unit today and got it and all accessories to work fine when the car is on.

My problem is, when i turn the key to the off position both the head unit and clock reset. Obviously this is because they're not getting a 12v feed with the key in the off position. I know I fiddled with the wiring heaps and might have knocked out a fuse but it isn't one that i could find.

Note that the only way i got all the accessories (clock, beeper) to work was to connect both the 12V battery line and the accessory power line from the car to the head unit's power line. It just doesn't work if it's connected up properly; the clock and head unit don't even turn on, and the open door beeper beeps reeeeally soft.

Anyone know of any fuses i might have blown? or have a solution for this?

Cheers :laugh:

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frx026 Proficient

frx026

Posted
Posted

Easy one, you have blown the constant 12v audio wire.

There are two possible locations for the fuse that will need to replace.

1 - under dash

2 - in the boot

Both are listed as "audio" fuses.

If you replace the fuse and it continues to blow, you still have a short in the 12v constant line behind the head unit.

govich Community Regular

govich

Posted
  • Author
Posted
Easy one, you have blown the constant 12v audio wire.

There are two possible locations for the fuse that will need to replace.

1 - under dash

2 - in the boot

Both are listed as "audio" fuses.

If you replace the fuse and it continues to blow, you still have a short in the 12v constant line behind the head unit.

believe me i've checked both those fuses 10 times and they're both fine :\ the fuses aren't blowing; the cd player turns on and works perfectly every time, it's just that when i take the key out both it and the clock reset - no 12v.

**JaR** Grand Master

**JaR**

Posted
Posted

yeah its not blown....

when we put the dvd player in my car, only way we could run the headunit and dvd player was to hook the accessories power wire to a switch, so we could flick between either headunit or dvd player, and it used to reset the clock and headunit, which in turn gave me the shits after awhile. so now i just have the headunit hooked up and it doesnt do it anymore.

its something to do with the accessories power wire... it isnt blown, its just the way you've got it connected i'd say.

govich Community Regular

govich

Posted
  • Author
Posted (edited)
yeah its not blown....

when we put the dvd player in my car, only way we could run the headunit and dvd player was to hook the accessories power wire to a switch, so we could flick between either headunit or dvd player, and it used to reset the clock and headunit, which in turn gave me the shits after awhile. so now i just have the headunit hooked up and it doesnt do it anymore.

its something to do with the accessories power wire... it isnt blown, its just the way you've got it connected i'd say.

yeah i tried many ways of connecting the accessory and battery 12v lines on the head unit and car ends and nothing would work except connecting them all together (as in all 4 wires together).. obviously this can't be the way to do it but it's the only way that works at the moment and i'm trying to figure out why. i didn't solder any of the connections just so i can take them apart later and fix it.

btw my car is a series 1.

cheers guys

edit: bit of thinking.. without the head unit connected, the only way the accessories would work was to connect the 12v battery and accessory lines together. however the clock would still reset every time i turned it off. why wouldn't the 12v line still be giving 12v when the key is out? on friday i'm going to whip out the multimeter and see what's going on with the 12v battery line. hopefully it'll come because at the moment the head unit turns on quickly and defaults to 87.5mhz FM and loud volume which is annoying.. and it's always 1am..

Edited by govich
**JaR** Grand Master

**JaR**

Posted
Posted

yeah mines S1 as well. hmmm

was it an aftermarket headunit in ur car before hand or are u replacing the standard one?

coz if it was aftermarket, seems to me whoever put it in before hand farked up somehow.

btw when your clock resets.... does it reset to 1:00

coz mine did. and i always thought that was kinda really weird given most clocks reset at 12:00 lol

govich Community Regular

govich

Posted
  • Author
Posted
yeah mines S1 as well. hmmm

was it an aftermarket headunit in ur car before hand or are u replacing the standard one?

coz if it was aftermarket, seems to me whoever put it in before hand farked up somehow.

btw when your clock resets.... does it reset to 1:00

coz mine did. and i always thought that was kinda really weird given most clocks reset at 12:00 lol

nah the thing is the previous unit was aftermarket (kenwood) but worked fine, the clock didn't reset. the unit was just old and stuffed and didn't display anything. so my conclusion is i farked something up and i'm trying to find out what cos i can't figure it out! yeah and it resets to 1:00 which is weird yeah..

govich Community Regular

govich

Posted
  • Author
Posted
hmm. maybe you did blow a fuse somewhere then.

but then again by all rights if you blew a fuse, it wouldnt go on at all. :laugh:

so im stumped for now.

exactly..

i spent 3 hours looking over fuses and looking for hidden wires etc

i connected exactly the same wires that the last head unit used (no more no less) and it doesn't work properly while the last one did :\

stumped for now...will see what i can do this weekend

RANDY Veteran

RANDY

Posted
Posted

Kinda would make sense though.

the only way the accessories would work was to connect the 12v battery and accessory lines together

Sounds like the 12v power is gone then. You put the accessory wire with the 12v wire, it will feed power to the 12v line... and the accessory power will be much weaker than the 10amp or whatever the headunit will want, so your door beeper goes dull.

When you turn the accessories off, it's not giving power to the 12v wire anymore, so you lose settings etc.

I'd guess that there is an inline fuse for the 12v constant power wire, which must have blown. That, or it's shorting out somewhere. My money is on a short, cause you say that when it's hooked up correctly, the door beeper is soft.

Get a multimeter onto those wires man. Test for 12v on both of those power wires, and even check that the grounding is 100%.

I used the stock wiring harness, and used all those wires, and it was fine. The only change was that the black ground from the head unit... which I put to one of those screw-bolts that hold the gearshift surround on.

govich Community Regular

govich

Posted
  • Author
Posted (edited)

see now that would make sense. i never thought of the battery 12v wire being shorted somewhere. this allows for a whole number of other fuses that could be blown - main lines from the battery as opposed to just audio fuses.

the battery 12v line is always 12v and the accessory line is 12v when the key is turned. of course.

i'll post pictures when i have a look.

thanks!

Edited by govich
RANDY Veteran

RANDY

Posted
Posted (edited)

Yeah good luck! I'm not so sure that the *main* battery wire is shorted, otherwise you'd have, like you said, a whole heap of stuff not working.

I suspect the 12v wire somewhere behind the dash, that feeds 12v to the clock, radio, and AC will be shorted or have an inline fuse blown. Your AC resets to 18 degrees or whatever, right?

But in any case, i'm willing to bet that your 12v constant feed to the HU is not giving out any power at all. I'd take the accessories wire off it ASAP, as the accessories may short with it and you could start a car-fire if you're not careful.

Edited by RANDY
govich Community Regular

govich

Posted
  • Author
Posted

yep, as predicted there was a blown fuse on the battery line. it's on the main panel under the steering wheel but it's one of the obscure ones in chinese characters (i can read japanese characters), i'll take a photo of it tomorrow in daylight.

the only problem i have now is the head unit resets after a while, but the clock doesn't so i know it's not the car. looks like i have more work to do :

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