Beegee208080

92 Civic LX, aftermarket radio/cd player

Starting about 5 months ago the radio would either cut out and in while driving, or not function at all. Its been getting progessivly worse, where now I'll be lucky to have it work for 30 minutes in a week of driving. I've also noticed when it does come on that the sound either projects from the rear only, the front only, or both.

I took the cd player out and unhooked the wiring harness from the back and the antenna. I thought I would test the wires going into the harness. I couldn't find my multimeter but I have a test light. I grounded the black test light wire and with the car started but not running, tried each of the dozen or so wires with the test light (both with the connector, and the original wires, see picture)



The 12 V Ignition wire (Red) lit up strongly, and the +12 Volt battery Wire (Yellow) lit up, but dimly. None of the other positive speaker wires caused the test light to light up, nor do I know if they are supposed to.

I am afraid I do not know what any of this information tells me, I'm rather new at this.

What should I test next to try to fix the radio, any advice/suggestions and explanations appreciated.


Also: After messing around with this, I noticed the lights on my dashboard clock were significantly dimmer. Also, everytime I turned the car off and on, the clock restarted to 1:00. What does this mean?



As an aside; my cigarette lighter hasn't worked in years. Since I had the wire harness for this out I tested it with my light also. There were 3 wires (red, yellow, black) and only one of them lit up the test light (i don't remember now which one, not black obv.) So I'm not sure what to check next on this; any suggestions again would be greats.

Thanks for your help

EsotericImage

iTrader: (8)

Electrical Gremlins strike again!

If your original radio harness has been cut, then who knows what could be wrong.

You can look in the service manual and see what goes where and then test it with your meter.

Beegee208080

Sorry if there was confusion. The original harness wasn't cut. I detached it from the new connector to test if there was a difference with the original harness wires and the new ones that those connect to. There was no difference

Beegee208080

I found out that the speaker wires shouldnt make the test light go on, because theres no voltage in those unless music is playing.

Would you guys reccomend checking the wires in the harness with a 9V battery to see if the wires to the speakers are good?

95accordCE6

Sounds silly, but what brand is the radio? I've found in some cases different brands react differently to certain things, for example a sony deck will turn off for 3 seconds and turn back on if there is a wiring fault, a pioneer depending on year will either do the same or stay turned on and go into safe mode. My personal way of diagnosing these sorts of things is to check for voltage drop in the wiring when the radio shuts off, check each speaker individually for a wiring issue or voice coil problem by attaching them one at a time and if the radio kicks off on one particular speaker then you know where to start. Be really observant because even a loose pin in the connector can cause an issue, and I've found some aftermarket harnesses to be really sloppy. Also do you have an amp and subs hooked up, and are the door/deck speakers stock? I'm also not sure about your car, but I've grown accustomed to the radio and cigarette lighter being on the same fuse.

Beegee208080

Thanks for the reply. Its a Sony CD player, no subs or amps, speakers are just OEM and were replaced ~9 years ago after they blew out

Update: I 9V battery tested the 4 pairs of speaker wires in the harness, I expected to hear a noise from the speakers but got nothing from all 4 sets.

Got a multimeter and checked resistance by probing ground lead to - speakerwire and red lead to + wire. All sets show '1' which i think is a blown circuit? Also was this tested correctly?

Given this information, whats the next move? If its a loose ground or something with the ground wire how do I test that?

Thank you for your help

Beegee208080

UPDATE:

took multimeter to

Red harness wire. Ignition off = 0V. Ignition on = 12.6V

Yellow harness wire. Ignition off = 1.7V. Ignition on = 4.08V

no harness speaker wire combo gives any ohm reading

the yellow wire should read 12V with ignition off right? what do you think is wrong here?

Beegee208080

Update 2: i know no one is answering me, but I could really use some help now.

i checked all the fuses with an ohmeter

ran a 9V battery test on the wires from the factory harness. 1 set worked, heard clicks, and gave about 60 ohms when tested. I tried again later and it stopped working.

the resting voltage on the yellow wire from above post is still only 4V with ignition on.

I did a continuity check on all speaker wires and no pairs had continuity. No wires had voltage except the red and yellow (as previous post)

Also my head unit no longer has power when plugged back in. I bench tested it w car battery and it work fine.

dash clock is dim, does not respond to the dimmer switch and always resets to 1:00 pm when restarting the car

I am at a loss now for what to try could i get advice?

95accordCE6

You should have a constant 12v at the yellow wire so I would start with that issue. Have you checked the 7.5a backup fuse in the panel under the hood? That would explain the clock resetting as well as the radio not coming on. I'm not 100% sure what the proper resistance is for oe speakers so I won't mislead you about that.

Beegee208080

I did check that fuse. its the only one that didnt give a reading.

However, since it said "backup" i just assumed it did nothing and was there as a spare

thanks, will update

95accordCE6

No prob, from what I understand it's a common problem. I can't say for sure if that would have caused the original cutting in and out of the radio, however you should have been able to hear a static sound from the speakers when you were testing them, and if one is blown that could cause the radio to shut off, especially at higher volumes.

Beegee208080

replacing the under the hood backup fuse fixed the clock and the yellow wire voltage (on and off) is > 12V

thank you! assumed backup just meant spare.....

rechecked continuity/resistance at the harness and still shows nothing. this could happen for what reasons im curious can it be bc of

-blown speaker
-short in the speaker wire (surely not all of them though)
-something to do with the ground, loose ground?

thanks, im trying to learn more about this stuff

Beegee208080

is the next step to check the speaker itself?

it seems logical to do a 9V test directly on the speaker. if that works, take one of the wires from the speaker off, attach a new one and check for continuity. if no luck, attach 2 new wires and repeat test?

if that works re wire the new wires back into the radio wiring harness, repeat for all speakers?

sounds like a pain in the ***. anything different i could try?

95accordCE6

That's a start. To check continuity you would be connecting the positive lead of the ohmmeter to one end of the speaker wire (at the radio plug) and the negative at the other end (at the speaker) and if that's done properly a 0 reading would indicate a break in the wire somewhere. Another way to check would be hooking up an test light in place of one speaker at a time and verify there is power there when the music is playing...I'd try this first with the rear speakers as they're usually easier to get to.

95accordCE6

Was replying to previous post. I would try this before doing all that

mike_1212

Why dont you just plug your stereo bck in and play music to the speakers? If 1 isn' workin you wont hear any sound from it... your yellow wire not having adequate power is why most of your problems happened. The pre-amp cant run all 4 speakers without having enough power to do it. This is why it would cut out. If it is still doin it after you have fixed the voltage on the yellow wire then. The stereo has been damaged by it. And needs replaced

mike_1212

The red wire or "switched" 12v. Turns everything on and off..... but the yellow is the 12v constant.... keeps presets... clock time.. eq settings.. powers the pre-amp etc... the stereo was running off of the wrong circut.... there is a chance its not damaged.. but youll have to plug it in and see

mike_1212

As for acc socket... or cig lighter... it should not b on the same circut as the stereo... otherwise if you charge your phone while listening to your tunes.... pop goes the fuse.... again...

mike_1212

As for the 9v battery trick... PLEASE dont do this! It can damage your speaker coils.... speakers are not like other electrical systems... all speakers are is electro-magnets.... the - and + symbols dont mean the same as typical power or ground.... they change polarity rapidly the move the speaker in and out thus creating sound... kind of like ac current... the rate in which they switch is rhe frequency... the amount of amps that are being switched is the volume..... so the faster the polarity switches the higher the frequency= more treble... the lower the frequency= more bass.. the more amps the louder the sound... when you connect a battery you are connecting a dc current to the electro- magnet... and bottoming out, or toping out the speaker... which can knock it off balance... or damage the paper backing the coil is glued to... it can even burn the coil itself...

Beegee208080

sorry didnt mention, this is the first thing i tried after getting power back to the head unit. no sound on any channel

going to try test light at speaker with music playing first as reccomended. will update

DOHCtR-V

Sometimes loose wires from the speakers causes this.
Check that all the speakers are connected properly/tightly, & not just taped together.
Loose wires cause decks to go into safe mode.

mike_1212

Did you test to see if you have sound coming out of the stereo?
Most problems with stereo wiring are found at the connections on the adapter harness... have you tested these? Has the stereo harnes been properly connected to the adapter harness? (With solder and shrink tubing)

mike_1212

From the photo looks like crimp style connectors... these suck! They corrode and cause intermittant problems like you have described... test resistance axross these connections.... (while wiggling 1wire or the other)

mike_1212

To do a proper test of your system you need to start at the head unit. It turns on... step 1 complete... step 2 play music.... leave power connections intact. Cut speaker connections... test across the head unit harness for power on speaker leads.... (purple and purple w/ black is one speaker etc...) if you have power there then touch these to the adapter connections and listen for sound at the speaker... if you have it ( which im sure you will) reconnect these properly with solder and insulate with shrink tubing... if you dont have power coming out of the head unit then disconnect for 5 min and try again... still no power. Replace head unit.

Beegee208080

sorry earlier I said this....

realized i wasnt playing anything. I have sound coming from the rear left speaker only.