Inline Fuse Blows and no power to H.U

MetisKnight · #1 08-15-2009, 09:54 PM

Hi all and I hope someone can help me out here. I picked up a 99F150 XLT 4.6 A.t that has a sony amp under the seat and an old aftermarket Pioneer head unit. P.O says stereo doesn't work. So I had a shop change the head unit to an new entry model and get it going. Turns out the inline fuse at the battery was blown and a new fuse was all that's needed. Well I needed to change the battery and after that the fuse was blown again and no power to the head unit.

Question is why would there be no power to the HD if the fuse by the battery is only to power the amp? I thought the HD was plugged into the harness in the dash and got power from there.

Any help would be appreciated.

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Low_e_Red · #2 08-18-2009, 02:44 PM

Double check how some idiot wired everything. Ive seen some STUPID things through the years. Second, check to see if you are getting 12v through Ign and B+ and double check to see if you have a strong ground.

Sundevil2188 · #3 08-20-2009, 03:34 PM

If you had a shop install it, they should trouble shoot it under their warranty? I know id look at it under warranty to find the problem, but charge you to fix whatever was wrong with it. The PO probablly taped the power wire for the amp for power for the HU, and probablly didnt use a wiring harness when he did it. Like low, I too have seen some STUPID things done behind dashes.

digitalamish · #4 08-20-2009, 11:23 PM

You might even need to trace the wires. If the casing rubbed off the wiring, it may be grounding somewhere and popping the fuse.

MetisKnight · #5 08-25-2009, 01:11 AM

Thanks for all the responses. I started double checking the wiring the other day. Under the driver rocker I found the amp cable and some other black cable. Contacted the P.O and he says that it used to power an old cd stacker. He just tucked the wiring there instead of removing. I did a double check on the fuse for the amp and whatcha know it wasn't blown. I took it out of the clear holder to get a real good look this time. So now I'm thinking the P.O did some wierd wiring with the remote cable to the amp as to why the H.U still has no power.

My brother in law says that some new decks have a power off fuse at the rear of the unit as a theft deterent. He says if you change batteries it pops and I need to check that. Has any body heard of this before and could it be possible?

Thanks again for the replies.

Sundevil2188 · #6 08-26-2009, 01:31 AM

yeah...most decks have a small fuse on the back of the radio.

You need to meter all fuses. Ive seen many, especially glass, that dont look blown but infact are.

MetisKnight · #7 08-27-2009, 04:05 AM

Hi all and thanks for the replies. After checking every freakin wire for continuity it turns out that it this was a faulty power button issue on the deck. Replaced the deck and all is well. Thats what I get for cheaping out on a deck.

Thanks again for all the suggestions.

Low_e_Red · #8 09-10-2009, 03:32 AM

Quote:

Originally Posted by MetisKnight

Thanks for all the responses. I started double checking the wiring the other day. Under the driver rocker I found the amp cable and some other black cable. Contacted the P.O and he says that it used to power an old cd stacker. He just tucked the wiring there instead of removing. I did a double check on the fuse for the amp and whatcha know it wasn't blown. I took it out of the clear holder to get a real good look this time. So now I'm thinking the P.O did some wierd wiring with the remote cable to the amp as to why the H.U still has no power.

My brother in law says that some new decks have a power off fuse at the rear of the unit as a theft deterent. He says if you change batteries it pops and I need to check that. Has any body heard of this before and could it be possible?
Thanks again for the replies.

Never in my years have I ever heard of a fuse on decks being a theft deterrent. If that fuse goes, its not a good thing most of the time.

js04screw · #9 10-02-2009, 02:01 PM

most of the time when the small fuse behind the radio goes the power supply in the unit is gone.

MetisKnight · #10 10-07-2009, 09:55 PM

I couldn't find this fuse behind the deck so perhaps that was the problem. The HU wouldn't power on which I assumed was the problem. I replaced the utni and haven't had any problems since.

Thanks for all that replied.