Alternator whine in speaker

[Mintyota]

Hi guys. I swapped out the OEM head unit in my 1999 Land Cruiser 100 for a aftermarket one, but now, I have, what I believe is an "alternator whine" in my speakers.

I know there are tons of threads similar, but they didn't help me. My wiring bypasses the "factory amp", because with the engine shut off, the sound quality is how it was before.
I read that unplugging the factory amp should do the trick, so I tried that. I read that the factory amp should be under the passenger seat but it wasn't. Not even under the carpet.

Under Front Passenger Seat

• Mintyota
• Sep 13, 2018

Under Front Passenger Carpet

• Mintyota
• Sep 13, 2018

Under Front Passenger Carpet

• Mintyota
• Sep 13, 2018

I checked behind the passenger dashboard, but nothing similar to an amp was there either...

Under Passenger Dashboard

• Mintyota
• Sep 13, 2018

So here I am, asking for your help. It seems as my Land Cruiser doesn't have an amp?
I am a car audio noob, so maybe i'm missing out something?

Here is a picture with the OEM head unit, and the back of it :

OEM Head unit

• Mintyota
• Sep 13, 2018

Back of OEM Head Unit

• Mintyota
• Sep 13, 2018

Any kind of help/advice is appreciated

 

[Pyrenees]

What harness did you install? From what I understand this is common with the amp.

 

[Mintyota]

I used the "Metra 70-1761 Radio Wiring Harness For Toyota 87-Up Power 4 Speaker" wiring harness

https://www.amazon.com/gp/product/B0002BEQJ8/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

 

[Pyrenees]

I just read that your location is Eastern Europe. Maybe those ones didn't have an amp? I've never seen this before.

 

[Mintyota]

Well the car was built in Japan. For the European market though. But everybody fixes this whining by bypassing and unplugging the amp, which kinda leaves me stranded?
From what I saw under the passenger seat, there weren't even loose cables, because I thought that initially, somebody took it.

 

[DutchCruiser]

From what I believe only very few European Land Cruiser came with the factory amp. So in your case the radio is connected directly to the speakers.

I had the same whining issue with my radio. My car didn't come with the original Toyota radio and I built in an aftermarket amp under the passenger seat. And with the new amplifier I got the whining issue. I also have the diesel version, so it might be a problem from the diesel alternators. The issue was bad grounding of the amplifier, so it added a cable for ground from the battery to the amplifier and that solved the problem. So in your case adding a new cable for the ground from the battery to the radio might help.

I also have a bluetooth adapter that I can connect to the amplifier which is powered by the 12V socket and it gives a very bad whining sound. So I am still working to solve this too. The whining noise is caused by an effect called common mode current, which means that there is interference on the ground connection which gets amplified by the radio. I even cleaned all the grounding points of the wire harness and it helped a little bit. So if I find a real solution I will let you know.

If you have any questions please let me know!

 

[Mintyota]

Thanks for sharing your experience! Will try that ASAP and will let you know what the result is. I will be adding an aftermarket amp soon anyway.

The whining is irritating when idling. When driving, because of wind, tire and climate noise, you can't really hear it. But I just want to find a permanent fix

 

[jerryb]

if you used the ground in the metra harness move it somewhere else. I wouldn't even put it behind the dash. I like the console and the seat riser rail. That should probably be the first step fix.

I can't believe how unbelievably cheap those are.

 

[Mintyota]

Just fixed the problem. What was causing the whine were the screws holding the double-din assembly in phe dash (single din radio + storage space in my case). I removed the screws, and just clipped the center console over. The clips on the console are strong enough to keep everything in place, and the whining is finally gone!

 

[REZARF]

Yep, you'll want to climate any group ding issues. Usually looks. Add g good grounds is key to cleaning up the signal.