* Pioneer Engine Whine / Ground Loop Fix*

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i upgraded to no noise //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

but for real i had 3 grounds on that shit and it never stopped

 
This is a great write up. I bought a 980p deck off ebay that was supposed to be like new, but had the blown pico fuse noise. I've been hooking up car stereo stuff since around 1992, so I'm assuming it wasn't anything I did. Anyways, I wrapped it a different way around the rcas that ended up failing later equaling no sound from the front right. This is a much better way than I wrapped, thanks for sharing!
yesssir

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i upgraded to no noise //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

but for real i had 3 grounds on that shit and it never stopped
it's cause you dont know what you are doing //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

 
So lemme get this straight cause this is new news to me. There's some internal fuse on newer pioneers connected to the rca's that blows & causes distortion if you don't ground out the rca's, right?

I recently installed a new pioneer deck. When I play radio I get engine noise, but when I use the ipod it's clear as a bell. Using a small 2 channel for front comps. I just assumed it was a bad antenna cable cause my last pioneer deck did the same thing with the tuner. Will grounding the rca's help me out at all?

 
So lemme get this straight cause this is new news to me. There's some internal fuse on newer pioneers connected to the rca's that blows & causes distortion if you don't ground out the rca's, right?
I recently installed a new pioneer deck. When I play radio I get engine noise, but when I use the ipod it's clear as a bell. Using a small 2 channel for front comps. I just assumed it was a bad antenna cable cause my last pioneer deck did the same thing with the tuner. Will grounding the rca's help me out at all?
Yes sir confirmed it with 4 shops. Had one shop tell me this and I blew it off so I asked 3 more and they all confirmed. Kinda crazy if you ask me.

 
So lemme get this straight cause this is new news to me. There's some internal fuse on newer pioneers connected to the rca's that blows & causes distortion if you don't ground out the rca's, right?
I recently installed a new pioneer deck. When I play radio I get engine noise, but when I use the ipod it's clear as a bell. Using a small 2 channel for front comps. I just assumed it was a bad antenna cable cause my last pioneer deck did the same thing with the tuner. Will grounding the rca's help me out at all?
no, it's grounding the chassis of the deck properly, and if you still do have noise then wrap the rca's.

 
This is the wrong way to fix this. IMO, the only reason to mess with it is IF the issue arises. If you don't "hot swap" your RCA's you will never have this issue.

The correct way is IF you have a ground loop, to open the unit and replace the pico fuse. I did it kinda half assed and soldered in a piece of 22ga instead of replacing the fuse because I didn't want to wait 2 weeks on a fuse to be ordered.

To do it the correct way you should have a magnifying glass on a stand, and a good iron with a fine tip, and some forceps or tiny needle nose pliers. Unsolder the fuse, then solder in the new one or a jumper (I don't recommend a jumper because the fuse is there for a reason, so proceed with a jumper at your own risk).

I tried your way at first, but after grounding my chassis, all my RCA's, and running all my amps, batteries, and HU grounds to the same place on the frame I still had interference.

Once I replaced the fuse the issue went away completely. 100% noise free no matter the signal source.

 
This is the wrong way to fix this. IMO, the only reason to mess with it is IF the issue arises. If you don't "hot swap" your RCA's you will never have this issue.
The correct way is IF you have a ground loop, to open the unit and replace the pico fuse. I did it kinda half assed and soldered in a piece of 22ga instead of replacing the fuse because I didn't want to wait 2 weeks on a fuse to be ordered.
Can you shed some light on this pico fuse? I swapped amps in my fiance's car and shortly after all the preamp outs on the DEH-P3900MP died. I still get some signal out of them, but barely enough to even register on my fluke.

I didn't realize there was a fuse in the unit, wonder if this is my issue..

(Edit: I'll go search deeper on this one too)

 
The pico fuse is on the circuit board. You will have to open the unit and find it, I'd recommend searching other DIY forums for a picture as my 960 has a way different layout.

It is tiny, I'd say .5mm x 1mm as a guess (it's been awhile).

If you can't find it at first, break out the magnifying glass. If you still can't find it, you may have to pay a few $ for a copy of the schematic.

Edit: after re-reading your post, I wonder if you don't have a larger issue. With the pico fuse blown you get a ground loop because your RCA's are grounding through the amplifier ground instead of the HU. The common complaint is just noise, nobody has talked about reduced performance.

Do you have your multi-meter on AC? It's not DC voltage just so you know.

Re-measure and let me know what you're getting. I'll throw a meter on mine this weekend when I have my tools home and let you know what I find.

 
The pico fuse is on the circuit board. You will have to open the unit and find it, I'd recommend searching other DIY forums for a picture as my 960 has a way different layout.
It is tiny, I'd say .5mm x 1mm as a guess (it's been awhile).

If you can't find it at first, break out the magnifying glass. If you still can't find it, you may have to pay a few $ for a copy of the schematic.

Edit: after re-reading your post, I wonder if you don't have a larger issue. With the pico fuse blown you get a ground loop because your RCA's are grounding through the amplifier ground instead of the HU. The common complaint is just noise, nobody has talked about reduced performance.

Do you have your multi-meter on AC? It's not DC voltage just so you know.

Re-measure and let me know what you're getting. I'll throw a meter on mine this weekend when I have my tools home and let you know what I find.
WRONG!!!

the pico fuse was not even in the Schmatic till late 06, not only is there no pico fuse on the board but it's inline with the ACC wire..

i cut them out, and ground the rca's.. allong with makeing sure the deck's ground and chassis of the deck has a goo vehicle chassis ground.

never had a problem with this EVER.

if you cant figure this out, you should really stop installing and kill ur self..

srsly.

 
it's cause you dont know what you are doing //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif
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Use these man PAC SNI35. Just do a google search. Works like a charm every time. Besides way cheaper than buying a whole new unit.
too late. i gave the pioneer to my bro. it was an upgrade for him so he's happy.

and i still have a slight whine with this unit, but i can deal with it.

 
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too late. i gave the pioneer to my bro. it was an upgrade for him so he's happy.

and i still have a slight whine with this unit, but i can deal with it.
jcHOE

check ur amp ground. allso it could just be a high S/N ratio amp...

sometimes it's in the amp, somtimes it's in the deck...

 
So lemme get this straight cause this is new news to me. There's some internal fuse on newer pioneers connected to the rca's that blows & causes distortion if you don't ground out the rca's, right?
I recently installed a new pioneer deck. When I play radio I get engine noise, but when I use the ipod it's clear as a bell. Using a small 2 channel for front comps. I just assumed it was a bad antenna cable cause my last pioneer deck did the same thing with the tuner. Will grounding the rca's help me out at all?
It's not really a "fuse". The name "Pico Fuse" is a misnomer... it's actually a micro-resistor that blows. It kind of acts like a fuse, but it isn't one.

The ultimate sign of a blown "pico fuse" is when there is engine noise even when volume == 0, and the drone is a constant volume at all volumes of the head unit.

Can you shed some light on this pico fuse? I swapped amps in my fiance's car and shortly after all the preamp outs on the DEH-P3900MP died. I still get some signal out of them, but barely enough to even register on my fluke.
I didn't realize there was a fuse in the unit, wonder if this is my issue..

(Edit: I'll go search deeper on this one too)
As stated in the previous explanation, it's not actually a "fuse", it's a micro-resistor. If you really want to fix it yourself, get your DMM, use the continuity setting, and go around... you should hear a beep on all the things that are still connected, when you find the pico fuse, it won't beep. It should be small, and in the back of the unit toward the pre-outs.

WRONG!!!
the pico fuse was not even in the Schmatic till late 06, not only is there no pico fuse on the board but it's inline with the ACC wire..

i cut them out, and ground the rca's.. allong with makeing sure the deck's ground and chassis of the deck has a goo vehicle chassis ground.

never had a problem with this EVER.

if you cant figure this out, you should really stop installing and kill ur self..

srsly.
You're wrong...

The Micro-Resistors have been used on Pioneer units since I believe maybe '04 and on? I'm not really sure. They've been using them for a LONG time (considering how fast technology moves). It's on the board, it's not inline with the ACC wire. That would be silly.

And, you're one to talk, Seth. You don't really have amazing installs under your belt.

 
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