1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

engine noise through aftermarket stereo

Discussion in '80-Series Tech' started by VETTE60, Nov 29, 2009.

  1. VETTE60

    VETTE60 New Member

    Messages:
    1,246
    Location:
    Pollock Pines,CA
    intalled an aftermarket (kenwood) stereo with wiring harness adapter in my 96 fj80 and am getting engine (distributor) noise through the radio. I have had experience with this in older radios and vehicles but never with the newer set ups. also note that I have the exact same stereo in all 4 of my vehicles and only getting noise in the landcruiser. . i know I can add a noise supressor, but I am wondering if something else would help like an additional ground. any input? thanks guys.
  2. firetruck41

    firetruck41 New Member

    Messages:
    5,735
    Location:
    Camas, WA USA
    I wires a headunit using a OEM amp integration harness, I tried a noise suppressor and changing the ground several different ways, nothing worked. I had to use plastic srews to attach the head unit to the dash supports (this insulated the head unit, from ground). I still got a tiny bit of interference. Once I finally wired it to bypass the amp, it all worked smashingly, no need for the plastic screws or any messing with ground.
  3. Paul_L

    Paul_L New Member

    Messages:
    549
    Location:
    Valencia, CA
    Did you disconnect the stock amp?
  4. phrogg4evr

    phrogg4evr Vote for Pedro SILVER Star

    Messages:
    2,700
    Location:
    NOVA
    Check your grounds, or re-ground the radio somewhere else.

    Good call on the amp;)
  5. phxtlc

    phxtlc New Member

    Messages:
    585
    Location:
    Plano, TX
    1. Directly ground stock amp to truck, don't use the common ground in the harness.
    2. New clean power to the head unit and/or amp.
    3. Lose the stock amp.

    You may also want to check the condition of your spark plug wires. If they're old or damaged they will emit radio interference.
  6. SBFJ60FIG

    SBFJ60FIG New Member

    Messages:
    1,001
    Location:
    Chicago!
    Not picking a fight here, and I'm not an expert by any means, but this is typically alternator whine, which you can confirm buy powering up some accessories that suck serious power (rear defrost, lights, power windows) and see if the noise changes in pitch.

    New spark plug wires should solve exactly nothing with respect to your issue stated here.
  7. VETTE60

    VETTE60 New Member

    Messages:
    1,246
    Location:
    Pollock Pines,CA
    actually it is a ticking noise and not a whine that is why i assume it is distributor not alt. but either way that does not matter. it is still an interfearance noise. ignition wires are brand new OEM.

    I did not know it has a stock amp. where would this be located? i am happy to disconnect it.

    the wiring harness i used only used 2 plugs and not three of them. i assume the third plug goes to the amp. all i need to do i guess is get rid of the amp.

    thanks for the input so far guys!
  8. TrickyT

    TrickyT Hate that mud... SILVER Star

    Messages:
    776
    Location:
    Mill Valley, CA
    The stock OEM harness was set up to use a couple of different radios, hence the presence of multiple connectors. AFAIK, all FZJ80's in the U.S. domestic market came with a "power" amp located behind the glove box and a "bass" amp and speaker located in the rear quarter panel, and thus used a single connector between the harness and the radio. (I used quotes around power and bass because the stock setup didn't provide much of either.) Aftermarket stereos have higher output amps built in and so you don't need the Toyo power amp. Thus you unplug this amp and then instead of using the original single connector from the harness to the radio, you use the other two connectors. The Scosche TA02B is the adapter you need, and this splices onto the connector that came with your Kenwood. With this setup, the finished adapter has a total of three connectors, two that connect to the OEM harness and one that connects to the stereo. And don't forget to unplug the OEM power amp.

    Hum/engine noise is a pretty common complaint if you try to leave the OEM power amp connected. Here's another thread describing a similar problem to yours: http://forum.ih8mud.com/80-series-tech/292855-clarion-cx609.html
  9. VETTE60

    VETTE60 New Member

    Messages:
    1,246
    Location:
    Pollock Pines,CA
    thanks. that is exactly how i have it connected now with that adapter, so now all i need to do is unplug the amp and i should be good.:beer:
  10. firetruck41

    firetruck41 New Member

    Messages:
    5,735
    Location:
    Camas, WA USA
    Actually, I believe you will need a different harness so you can plug directly into the speakers at the amp location. By unplugging the amp you no longer are sending anything to the speakers. There are writeups about bypassing the amp, and I have a long PM trail with another mudder, about it. I will try and find it and post tonight.

    EDIT: The method I used is correct for LX450s, but not necessarily for LCs. Further info in posts below.
    Last edited: Dec 1, 2009
  11. TrickyT

    TrickyT Hate that mud... SILVER Star

    Messages:
    776
    Location:
    Mill Valley, CA
    Sorry, but I disagree. If you try to use just the single OEM harness connector that was used by the OEM radio, then you'll wind up with no connection to the speakers. But if instead you use the two other harness connectors, these have direct connections to the speakers. I only have a 1997 EWD for reference, but I'm 99.9% sure that a 1996 FZJ80 is the same. Look on page 158-159 and you'll see that radio connector R1 is wired directly to the front speakers and connector R3 is wired directly to the rear speakers. Connector R2 is used to connect the OEM radio/player to the OEM power amp and is not used in aftermarket installations. You need to unplug the power amp so that it's no longer connected to the speakers. Having both the OEM power amp and the aftermarket HU connected to the speakers at the same time is what causes the interference.

  12. spdwaver1

    spdwaver1 New Member

    Messages:
    1,742
    Location:
    Santa Clarita, CA.
    I also was able to bypass both amps (mine is a '91), simply by unplugging them. This did not require a new harness direct to the speakers.


    The only time you will need to run any extra wiring is if/when you decide to add an aftermarket amplifier or two.
  13. firetruck41

    firetruck41 New Member

    Messages:
    5,735
    Location:
    Camas, WA USA
    OK. didn't work that way for me, and some others, but if it works, it is even easier!
  14. VETTE60

    VETTE60 New Member

    Messages:
    1,246
    Location:
    Pollock Pines,CA
    it worked that way plugged into the other two plugs on the factory harness with the adapter. just finnished. used the aftermarket harness, got both new power leads, and a ground (not from the harness), and unplugged the two connections from the amp, and unplugged the sub amp in the rear. still have a nit of ticking at full blast, but mostly gone. thanks for the help fellas.
  15. firetruck41

    firetruck41 New Member

    Messages:
    5,735
    Location:
    Camas, WA USA
    My 96 LX is definitely different. R 1 and R 2 do not connect directly to the speakers, and in fact there is no direct wiring to the speakers from the head unit (per the EWD).

    To bypass the amp, and to eliminate the interference, I had to wire from the head unit harness, to the S 15(A) and S 17(C) connectors at the amp, behind the R side dash speaker. I also disconnected and removed the amp. I used the aftermarket harness that came with the aftermarket head unit to plug into the head unit (obviously), and then I used Scosche TA02B harness (~$10 at Walmart), to plug into the S 15(A) and S 17(C) connectors at the amp. I had to splice the two harnesses together with extra lengths of wires to reach the R side of dash. Works like a champ.

    Kaoscruizer ([Canadian?] 97 LX) wired it the same way, after I gave him some direction via PM. Figured I would include this here, in case someone else has a question about it.

    Attached Files:

  16. TrickyT

    TrickyT Hate that mud... SILVER Star

    Messages:
    776
    Location:
    Mill Valley, CA
    The EWD for the LX audio system looks completely different than that for the FZJ. And I see that you've even got an ECU for the antenna. Kool. Good to know about this key difference between these vehicles.

    Edit: FZJ80's also have an antenna ECU. See page 118 of the EWD.
    Last edited: Jul 26, 2010

Share This Page