2005 Altima Head Unit Install Problem

[black02z]

Hey everyone, new user here. Ive learned a lot reading these forums without ever having to post but now I'm looking for some help with a problem I've never dealt with before.

I was installing a Dual XD250 head unit (not my suggestion) for a friend in his 2005 Nissan Altima with the base audio package. I wired it up normally, turned the key on and everything works how it's supposed to.

Now here's where the problems start. When I go to start the car, all the settings reset as the head unit loses it's memory. So I grab my multimeter and start checking the wiring. Key on, the fused yellow wire has battery voltage (fuse is good), when starting the engine the voltage drops to approximately 9v, the black wire is always grounded, but the red wire completely loses it's power, 0v, when cranking the engine over. As soon as the car is running everything works normally until the car is started again.

I'm at a loss as to why the head unit resets every time even though the yellow wire maintains it's voltage and should be responsible for maintaining the memory. I know it's a cheap head unit, is it possible there's a problem with the head unit internal memory? If anyone has any suggestions, I would really appreciate it.

Thanks

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[pickup1 5,000+ posts]

Yellow wire is dropping too much voltage..... that's what holds the memory.... thinks it's unhooked when started..

 

[BryceHinton]

What pickup1 said.. red (accessory) is supposed to drop to 0v when the car is started. The yellow (constant) wire should always stay 12...

If your constant is dropping to 9v first thing I would do is check that your battery is in good condition (12.6v when the car is off, at least 13.8v when the car is on), if that checks out ok, then check the fuse in your vehicle that is in-line with your radio. Worst case you would just run your own constant wire..

 

[black02z]

I figured the red wire should be dropping to avoid drawing too much from the battery while starting the car. The battery tests good and both fuses are good. I guess my question is why is the yellow wire dropping voltage so much and how do I fix it. I would really like to get this figured out since the stock head unit doesn't have this memory problem.

Thanks for the quick responses, and if it comes to it, I can run a new constant wire. I guess the answer just isn't exactly what I was hoping to hear since it's not my car.

 

[black02z]

I figured the red wire should be dropping to avoid drawing too much from the battery while starting the car. The battery tests good and both fuses are good. I guess my question is why is the yellow wire dropping voltage so much and how do I fix it. I would really like to get this figured out since the stock head unit doesn't have this memory problem.

Thanks for the quick responses, and if it comes to it, I can run a new constant wire. I guess the answer just isn't exactly what I was hoping to hear since it's not my car.

 

[BryceHinton]

Test the battery while starting the car. The constant wire (if everything is hooked up correctly) will mirror the batteries voltage drop (if any) while the car is starting

It could just be that dual headunits dont like 9v.. at that point youre just talking about internal parts and the quality of the unit

 

[Side Show 10+ year member]

wire it up correctly.... the yellow wire (on headunit loom) isn't connected to the rite wire inside the dash.

duel headunits = crapola (check if that has any fuses too)

 

[CrossoverOre 10+ year member]

test voltage at the battery when run through the crank cycle and see what you get. If it drops to 9 there then you may have to do some electrical upgrades. if not you could always rewire direct to the battery.

 

[jrouter76 10+ year member]

I would agree with CrossoverOre bypass ALL the Headaches and wire the red and yellow(Memory wire) tie them together and wire them Directly to the Battery,I know some people like to wire through the wiring harness and proper,But that can and does not go right sometimes..case in point above problem.

)

 

[CrossoverOre 10+ year member]

do not tie the red into the yellow its ok that that one loses power. just rewire the yellow to the batt.

 

[jrouter76 10+ year member]

I tie them both together so I don't need the key to play my radio,thats just me,some time I go to my car and don't always have my keys handy and want to play some music...there's nothing wrong either way...never had a problem this way just make sure that thwire from the battery to the power and memory wire are fused with the proper fuse.

 

[Side Show 10+ year member]

drain your battery much ^^^headunit stay's on when cars off?

I would only tie them together to test a unit

 

[black02z]

Thanks for the help everyone. I am going to attempt to rewire the yellow wire to the battery at some point this week and I'll let everyone know how it goes.