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Radio wiring harness question

Discussion in 'EEK! - Every Extended-K Car' started by twankowski, Mar 28, 2020.

  1. twankowski

    twankowski Active Member

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    Hello,

    I'm spending my (abundant) time at home these weeks fixing up an '85 K-car wagon. I have lots of simultaneous tasks going on at once as I'm seemingly always waiting for another Rock Auto delivery. The latest issue is radio wiring.

    When I got the car a few weeks ago it came with a crappy aftermarket unit (just set in the dash) with two oversized speakers simply resting in the 3.5" dash recesses. Worse yet, someone cut off the factory harnesses and went nuts with scotch locks and crimp connectors.

    I bought a set of harnesses on eBay (to plug into an OEM radio) and yesterday afternoon tried to show off my soldering and heat-shrink skills. One thing led to another, and I finally ended up removing the entire dash for ease of access (and to clean 30-plus years of filth). Here's the issue:

    After a bunch of online research and cross-checking on the car, I came up with a detailed wiring schematic. In the case of this car, the solid red wire should be 12V constant (battery) and the red with white stripe is 12V switched power. My issue is that the 12V constant power (red) is kaput. The 12V switched is great. Radio fuse (10A) is good.

    In the previous install, the last guy ran a dedicated 12V hot, which was spliced in to a hot (pink) wire behind the steering column. While he did a pretty sloppy job, it appears he, too, had the same issue with lack of constant power.

    A few questions:

    1. Since the existing red wire for the radio is dead, is it OK to tape/seal it and bypass it like the last owner? I really have no desire to open up a 35-year-old bundle to chase a dead wire. I can re-solder the last guy's bypass job (by the steering column) and neatly package it up with the existing wiring bundle and into the OEM style plug-in harness.

    2. Is it likely the dead red wire is solely for radio power? In other words, if I bypass it as described above, no harm, no foul?

    Thanks for any advice you can offer. I won't even go into the spaghetti-like mess where the rear speakers should reside...
     
  2. ImperialCrown

    ImperialCrown Moderator
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    Can you run a 'battery' power wire for clock/station memory from the cigar lighter socket?
     
  3. twankowski

    twankowski Active Member

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    Sure can. Much closer, too. Still wondering if the dead wire in the current bundle is required elsewhere...or if I just tape it up all will be OK. Good suggestion on the lighter lead!
     
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  4. valiant67

    valiant67 ...

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    It is almost guaranteed there is more on that circuit than just the radio constant power. But it is possible the issue is after the circuit splits to power the radio. First step would be to look in the owner's manual and see what else is on the fuse and see if those items work.
     
  5. Bob Lincoln

    Bob Lincoln "CHECK FAULT CODES"
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  6. twankowski

    twankowski Active Member

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    Thanks, Bob. That PDF (along with some other research) is what I used to draw up my schematic. Admittedly, a few items were a wag as all the colors weren't a prefect match. Here's what I drew up (note - my application is at the bottom of the image; the circles represent my front speakers and the squares are the plugs). The build date on this particular wagon is June 7, 1985.

    upload_2020-3-31_10-2-35.jpeg
    For all four speaker locations, I actually put eyeballs on the wires at each location, so those have to be correct. The only discrepancy I saw was the chart shows Dark Green for LF+ while the existing wire is dark green w/ a white stripe.

    For the rest of them, I know Red w/ White Stripe is switched power (confirmed with meter). I'm assuming the solid red in my bundle is supposed to be 12V constant. This is the dead one, which the last guy bypassed with a direct splice from the pink 12V constant wire behind the steering column. There is no reference to orange or black w/ yellow stripe in the above chart (both have only about 0.5V switched power), but I read on another site they could be for dimmer and illumination (J & K above - says do not use).

    I'm thinking I'm going to tap a new constant power lead from a hot source - probably the lighter feed - and solder it into my new male gray plug.

    Thanks for the assist!
     
  7. twankowski

    twankowski Active Member

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    Solid advice, thanks. The manual shows cavity #9, 10A, Radio. Nothing else. Fuse appears good, but now I'm going to double-check it.
     
  8. valiant67

    valiant67 ...

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    The reason J and K say do not use is an aftermarket radio won’t use the factory lighting controls.
     
  9. twankowski

    twankowski Active Member

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    Ah, so...makes sense. In my case, I always use OEM radios from my stockpile or from eBay. That's why I'm wiring in the factory-style male harnesses to plug into a Chrysler radio. The later units from the mid-90s don't sound half-bad with new speakers and I just prefer the original look.
     
  10. 85lebaront2

    Level 2 Supporter

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    Ok, fuse #7 feeds the red wire, circuit X1, the horn relay feed (violet wire circuit H1) is also on it, Lighter is the same so tapping it there will be the same fused circuit, key in buzzer or chimes, electronic cluster (if used) door open and if a wagon, liftgate ajar. If the horn works then it may just be the wire is open and tapping the lighter power feed will solve it.
     
  11. AllanC

    AllanC Well-Known Member

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    I believe you are on the proper track. It took some time but I was able to find wiring diagrams for 1984 K car for the radio installation and the X1 splice. Images attached. It appears the X1 splice is in the harness, rear of instrument panel and under the point where the instrument panel meets the windshield. Hope this helps.

    Radio Wiring 1984 K Car.jpg Radio Wiring 1984 K Car X Splice.jpg
     
  12. twankowski

    twankowski Active Member

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    85lebaront2 and AllanC,

    Thanks for your effort here. This stuff is gold. Really appreciate the time you took helping me with this. I have a few things to check now.

    One thing that comes to mind immediately is when I first started inspecting the wiring, the physical fuse box was detached from its mooring (the L-shaped bracket it slides onto) and fuse #7 (20A, labeled lighter/belts) was gone. I swapped in a different 20A fuse and checked the bullet connector for the lighter and sure enough had 12V hot. Until you posted, I didn't realize all the stuff on that circuit. Just grabbed the owner's manual and it says that fuse covers:

    - Horn and horn relay (horn didn't work...and now I see why)
    - Lighter
    - Glove box light
    - Liftgate ajar light (this is weird because when I first got the car, the "gate ajar" warning was constantly illuminated and as a precaution I bought a new trunk open warning switch - but haven't installed it yet. Maybe it defaults to a complete circuit?)
    - Radio memory
    - Key-in/Headlights-on warning

    I mistakenly thought the 10A fuse (cavity #9/radio) was primarily for radio power. I was quite wrong. This could simply be a case of a missing fuse! Why it's gone I don't know...

    Thanks again for the info and schematics. This is all pretty new to me, as I generally prefer messing with the greasy and oily parts!
     
  13. 85lebaront2

    Level 2 Supporter

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    No problem, we are all here for information and help. It goes both ways too.
     
  14. AllanC

    AllanC Well-Known Member

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    One of the power feeds created at the X1 splice travels to the instrument cluster, right side. There is a circular connector that mates to pins arranged on the circuit board. Power goes through pin H, goes to the liftgate ajar warning lamp. Return circuit goes back to the circular connector and onto the rear of the vehicle. The liftgate warning lamp switch provides a ground to the circuit. This works in similar fashion as does the door jamb plunger switch at the door hinge area that controls the dome lamp. Open the door and the switch is released and completes the circuit.

    Check the switch for being broken or stuck. With liftgate open you should be able to depress the switch and see the warning lamp on the instrument panel turn off.

    Fuse #9 purpose is to provide switched power from the ignition key activated switch (ACC and RUN position) to the radio chassis. This provides power for the receiver, speakers, etc. No other features power through fuse #9.
     
  15. ImperialCrown

    ImperialCrown Moderator
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    I have found battery power fuses missing before. It is usually from someone trying to stop an unknown battery draw condition and the subsequent dead batteries.
    Lighter socket shorts can also blow this fuse. Glad you found it.
     

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