• Welcome to the Contour Enthusiasts Group, the best resource for the Ford Contour and Mercury Mystique.

    You can register to join the community.

f34 good, no HU or interior lights?

K

KAOS_3.0

Hard-core CEG'er
Joined
May 16, 2008
Messages
2,997
Location
SE / CLT,NC / ATL,GA
so... this is driving me crazy

I've got a 6amp 12v power supply hooked into the interior fuse box at fuse 34, to power up the interior for testing stereo and lighting mods I'm working on while the engine is out and waiting for a clutch.

everything was dandy for over a week. I go out today, and no good. power supply lights up the dash, the cig lighter, the strobes, ect, but nothing that is comming from F32. the fusae is good, and the courtisy light relay clicks when you push in or let out the door switch.

no overheadlight, no trunk light, no head unit, nothing from that spot.

any suggestions?

this is making me insane as I type

thanks for the help guys
 
uh, no battery, or engine, or pcm,

I have a 6amp/12v power-supply providing juice for the interior electronics.

the circuit that the head unit and courtesy lights are on is no longer working. it was working earlier on the power supply, but it no longer is. something has gone bad on me. need to figure it out before I start driving around in it again.
 
Well, seems to me that if you tested for voltage potential (difference) from ground to the "output" side of F34 and got nothing, but then tested again on the opposite side of f34 (battery side) and get a showing of differential voltage then your fuse certainly would be proven bad.

Have you done this??

You say "F34 is good".. how do you know? What specific tests have you done?

Half-splitting a circuit will get you to the problem very quickly.
 
well the fuse is not blown, and if 12v introduced at that point, power gets to everything elkse in the vehicle, just not items after that socket in the car.
 
so ray, basically what your saying is to check for continuity on both sides of the fuse circuit?

that doesn't exactly change anything, as I had the power going into the fuse panel at fuse 34, with a pair of spade lugs.

I'm thinking this could be the origin of the problem in the first place, but I'm not sure why, when the smallest amp rating in the car is 7.5 amps and it's a 6 amp power supply.

the last thing I messed with before it quit was the trunk light the night before, any chance a short there could have crippled the circuit else were? or would this just be coincidence?
 
Well, is the trunk lighting on F34?

IF so, a short there would blow any fuse you've got in there instantly.. and if you jump a fuse with a solid lug then you're going to be pulling max current from your power supply and ITS toast, too.

I am not saying to check continuity anywhere..

I said to check for potential (voltage) not continuity (resistance)

Look..

Battery ---x--- F34 ---y--- YOUR CAR PROBLEMS

You need to check from x to battery positive and if you have a ZERO volt difference then that means at BOTH POINTS of your meter (the battery and the x) that the voltage is the SAME.. which is good.. you WANT voltage at that side of the fuse.


Now, meausure from Y to the battery positive... do you still have a zero readout? if so, then that fuse is fine. If you have a readout that looks like about 12V then that is showing the DIFFERENCE between the battery and the "y" so you have 0 volts at y. Problem with the fuse.

You could also measure CURRENT DRAW in that circuit by placing the meter in series.

(Battery ----METER POS <--> METER NEG----F34----interior.)

So that the entire passing of power goes THROUGH the meter... that will show the current draw and you SHOULD see none if your lights are all off, etc.. if you are still showing current being pulled then you have a drain somewhere.. if its a dead short it will be in the 500-900ma or even in the AMP range... that's only a 6A charger, remember!
 
I ran a similar test to see if the socket was fried, like

top leg of socket---negative charger---positive meter---negative meter--- positive meter--- bottom leg of socket

that kept showing 12v, sooo..... idk what that really means.

I'll run the tests you said and get back with some results later this evening

thanks for helping out
 
had the ground going to the chassis in the door hinge area and the positive wired into the spot for f34.

hence why I'm wanting to think it's a problem with the fuse panel
 
I would say to try and hook the charger up where the battery goes, that way you can see if maybe the fuse box is bad inside the car.

Reason I say this is because it may have overloaded the circuits inside there with the high amp draw from the sub.

I had a weird electrical problem once... I got into my car and tried to start it, but all I heard were super loud pops and bangs from the speakers and the engine not turning over a bit. I thought my battery had died, but got back there (it's in the trunk from the previous owner), and it was a loose hot on the battery. What happend was I went to add the power wire for my amp, and I thought the easiest way was to crimp a ring onto the amp's hot and take the nut off the terminal and put it there... until I got to Walmart and saw a nifty Scosche (spelling... I could care less!) battery terminal that was more like a Y adaptor... it went on the battery terminal and then had 2 holes to put up to 4 guage wires into, one for the car and one for the amp. Cut the original terminal off (no way to remove it off the cable without cutting), and put that on, only for it to just break after a month or so from it being pot metal. So I had to go get a proper battery terminal and a ring for the power, and put that on.

The ring was held tight because the terminal was tight on the battery, but the car's hot fell out. So when I started the car, the starter pulled power through the amp, which could handle it, then must have pulled it through the RCAs or remote turn on, then through the head unit and through the tiny contant power lead (since the switched lead for the radio is off during crank) and through the fuse box. Ended up frying the amp inside the head unit. Everything else survived and I fixed the connection for good! Guess the speakers popping was the indication of me destroying the head unit's amp. Wasn't too mad cause it was an old Pioneer cd player I had for YEARS (just a little newer than the one you have), and was the 2nd to the lowest end when I did buy it. So it wasn't such a big loss, gave me an excuse to get a new one since I had been holding out because there was nothing wrong with that Pioneer. Went out and bought a 7600MP to replace it, and I still have that to this day (4 years later, in my Audi).

So anyway, moral of my story is... if you provide power in the wrong place, something is going to screw up.
 
Last edited:
yeah, thats kind of what I was thinking too. thats crazy your amp could handle that current draw, I've got a memphis D-500 over here that keeps blowing up. it's got a cap on the inbound power circuit that is underrated, I've replaced it twice, but it's getting old. next time I fix it, I'm selling it off for cheap.

the power got in the wrong place in a series of small skrew ups. first, I was running the led lighting, so I ran a 9 watt 12v supply to the panel, which actually ran the head unit at low volume. so I put in the door speakers, but wanted to test them out better, so I hooked the amp up. then I ran the subs, and for some reason didn't realize that pulling the full 6 amps backward through the fuse panel might be a bad idea.

still not sure how 6 amps could fry anything in a car with no circuits smaller than 7.5 amps though....

oh well, I'm going out to hook the charger up to the batt terminals and poke around with the multi meter. I'll get back with some results in a bit, thanks
 
Not only did the amp handle that (An older MTX 300W RMS @ 4ohm I was using at 150W RMS @ 8ohm on an 8ohm 15" RF 180W RMS sub), but it worked after, and is currently in my Audi (as well as the 7600MP) powering a 30cm (12") Kenwood 4 ohm 300W RMS sub, and sounds great for my taste.
 
thats awesome, I havent messed around with many MTX amps. only mtx stuff I've got is some blue thunders that I picked up after mtx bought Xtant, because those old Xtants just looked cool as crap back in the day.

I've got an american pro that seems to be idiot proof though, that things been driving the system in my bedroom for a long time. it gets used as a test amp alot, and in so doing, has seen some crazy ohm loads, but hasn't ever gotten hot enough to blow. if it did though, they're 35 bucks at besco or a similar wholesale distributer

anyway, I figured out the fuse problem. seems shoving big wires in the fuse panel just spread the connectors, so the fuse wasn't making contact. shoved a jumper wire in for now and it works. all I have to do now is pop the fuse panel open and crush the connectors back down some.
 
You must log in or register to reply here.
Back
Top