It doesn't matter what you unplug if its shorted out before the bulb its still going to blow a fuse. You need to find out where is shorting out.
Courtesy Fuse keeps blowing
- Thread starter Tony_SS
- Start date
Without the fuse in, see what your resistance between the 12v side and ground side is on the extra cigarette lighter plug. If it's 0 ohms then somewhere in your wiring you have a wire touching ground. If you do then that's what I'd start looking at.
You said you wired an amp, I'm assuming you ran separate wire for +12v? If you wired it directly to the same line as the cigarette lighter, that's probably your problem... most amps have built-in capacitors for reserve power on instant power draws (bass drum, etc.). Without any resistor to gradually charge the capacitor, there is a high instant draw, which can blow that fuse. I'm not saying you've wired it this way (you seem pretty sensible, i.e. knowing a larger gauge wire is good for an amp), but I've seen some pretty strange wiring jobs and just wanted to cover the bases.
If the amp isn't wired to that circuit, I'd look at any wiring you added like 79Landau mentioned. I've put in a ton of stereos over the years (many just simple aftermarket decks, etc.), and depending on how everything is hooked up - like if the wire is twisted together/taped - you could get a stray strand off the battery lead and it will short to ground even though you thought you've taped everything up nice & tidy. If you have any constant 12v leads loomed/taped together with ground wires, try separating them and see if that solves it. If not I'd start tracing the +12v wire back to its source to see if it's chafed on anything.
You said you wired an amp, I'm assuming you ran separate wire for +12v? If you wired it directly to the same line as the cigarette lighter, that's probably your problem... most amps have built-in capacitors for reserve power on instant power draws (bass drum, etc.). Without any resistor to gradually charge the capacitor, there is a high instant draw, which can blow that fuse. I'm not saying you've wired it this way (you seem pretty sensible, i.e. knowing a larger gauge wire is good for an amp), but I've seen some pretty strange wiring jobs and just wanted to cover the bases.
If the amp isn't wired to that circuit, I'd look at any wiring you added like 79Landau mentioned. I've put in a ton of stereos over the years (many just simple aftermarket decks, etc.), and depending on how everything is hooked up - like if the wire is twisted together/taped - you could get a stray strand off the battery lead and it will short to ground even though you thought you've taped everything up nice & tidy. If you have any constant 12v leads loomed/taped together with ground wires, try separating them and see if that solves it. If not I'd start tracing the +12v wire back to its source to see if it's chafed on anything.
Tony_SS said:
something is odd about that stereo wiring. I like to avoid the factory wiring altogether and run the + constant power and + ign power directly to one of the "open" pins in the fuseblock and use an in-line fuse for safety. By what your are saying above it sounds like yours is wired the same way but somehow it must be tied into the courtesy line somewhere. The wiring on your deck may be different but most I have done are
Red= 12v constant
Orange= 12v switched/ign
Yellow = remote wire to the amp
Maybe start with removing the amp and see where you are at, then maybe next the stereo. Tracing a wiring problem is never fun. I have an intermittent ignition based humming sound ( gets louder the fast the engine revs ) coming thru my stereo maybe 3-4 times a year that drives me nuts because I cannot find it.
I ran 10g wire from the battery to the amp in my trunk, with an inline fuse. The blue wire goes from the back of the head unit to the amp. I'm going to unhook the those wires and see if I cant get the head unit to power.
But am I correct in that the head unit should power without the courtesy fuse in???
According the Alpine manual, yellow (thick wire) goes to the battery term on the fuse box, and red goes to the ign. Thats the way I have it hooked.
I have totally unhooked the cig lighter wires.
But am I correct in that the head unit should power without the courtesy fuse in???
According the Alpine manual, yellow (thick wire) goes to the battery term on the fuse box, and red goes to the ign. Thats the way I have it hooked.
I have totally unhooked the cig lighter wires.
I've seen some turn on but won't do anything else, but the majority I've worked with won't power on without both connected. Different companies make their units differently... that Alpine wouldn't be the first I've seen with a heavy battery lead... the manual probably mentions going right to the battery or a source capable of high current, doesn't it? I've wired them like any other radio before, mainly because I was running an amp from the start (the heavy gauge wire is for the internal amp of course). The power wire for the amp shouldn't have any effect since it went straight to the battery, and the blue trigger wire was fine too.
Did you disconnect the wiring for the lighter plugs at the source, or just at the plugs?
Did you disconnect the wiring for the lighter plugs at the source, or just at the plugs?
I just unhooked the cig lighter wire where it plugged into the plug.
I have the exact same head unit in my truck, wired into the factory harness w/o any issues.
I have the exact same head unit in my truck, wired into the factory harness w/o any issues.
I had the same problem with mine. I always had to change the fuse before the yearly safety inspection because the horn runs on the same circuit. Changed out the radio and haven't had any problems since.
Tony if you haven't gotten any where by Thursday, I'll be going to pick my wife up from the airport. I get out of class at noon and she gets in at 7:45....depending on your schedule, maybe I can stop and take a look. Sometimes a fresh perspective helps a lot lol
Get yourself one of these. It will come in realy handy more than once.
It can be a real pain tracking down a short. I've used this on everything from Airstream trailers up to garbage trucks at work.
It looks like your on the right track, reverese what you've changed and work your way back
KD Tools 2524 Short Circuit Detector KD2524
It can be a real pain tracking down a short. I've used this on everything from Airstream trailers up to garbage trucks at work.
It looks like your on the right track, reverese what you've changed and work your way back
KD Tools 2524 Short Circuit Detector KD2524
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