Aftermarket Radio Installation Simple Inquiry

[PJMack]

Hello guys, I'll start right off the bat by explaining that I do not have a lot of experience with working on my Pathfinder or vehicles in general. That said, I have hands and I have common sense and if anyone here has the patience to help me answer some simple questions about my vehicle it would be greatly appreciated. I noticed there was already a thread somewhere on here about an aftermarket radio not performing routinely, but the source of my problem seems to deviate entirely from that and I don't feel like trying to piggyback off a thread that already found a solution.

 

I have a 1994 pathfinder, its got some wear and tear and I decided I wanted switch the stock cassette/FM radio out as it only seemed to give sound in warmer conditions. It's never given me a display, and if it gets cold enough the audio cuts out so that you can only faintly hear it in either the front or the back speakers. After I bought a cheap aftermarket FM/digital media radio that I hooked up to a wiring harness that not only wouldn't display but wouldn't even turn on, I'm starting to think the jumping between front and back speakers and cutting audio has to do with the amplifier which I can fix another time. Right now, I'm thinking the fact that neither decks give me a display and the entirely digital deck won't even turn on has to with a lack of power. I checked the fuse for the radio, it's 10A (recommended) and intact. The only other thing I can think of is that the ground or the connection to the battery is shorting somewhere. I can buy a voltometer and verify this but even if I do find out it's not getting enough volts, how can I fix that? Can someone help me?

[Slartibartfast]

If it was shorting, the fuse would be blown. It sounds more like an open circuit to me. What sort of harness did you use? If it was the type you have to solder yourself, check the connections and make sure you put the right wires together. Messed up speaker connections shouldn't prevent the deck from powering up, but I would look at the constant +, switched +, and the ground, and make sure they're hooked up correctly.

 

If you get a voltmeter (recommended), you can check for 12v from constant to ground, and 12v from switched to ground with the ignition on. You can also check for continuity from the ground wire to a known ground (I'd just use the metal brackets under the dash). It won't fix anything on its own but it'll help narrow down the issue.

 

Speaking of narrowing things down, you could pull out the radio and hook it to the battery with test leads, and see if it comes on then. It would suck to pull all the wiring out just to find that your new radio is defective.

 

Bypassing the amps is easy. We've got a couple writeups on it, one of which I did. Even if your amps are fine (mine were), your stereo will sound much better without them.

[ahardb0dy]

just remember most aftermarket decks use 2 power leads as Slartibartfast mentioned, one goes to constant power the other to a switched power source, also there is no ground wire in the factory radio harness the new radio needs to be grounded to the metal on the side of the radio, or where ever you can get a good ground from near the radio.

 

The display on the new radio if connected properly should at least come on, it should not have anything to do with the stock amplifiers.

 

Double check your connections before moving ahead.

[PJMack]

just remember most aftermarket decks use 2 power leads as Slartibartfast mentioned, one goes to constant power the other to a switched power source, also there is no ground wire in the factory radio harness the new radio needs to be grounded to the metal on the side of the radio, or where ever you can get a good ground from near the radio.

 

The display on the new radio if connected properly should at least come on, it should not have anything to do with the stock amplifiers.

 

Double check your connections before moving ahead.

I appreciate the responses. The ground wire was the issue. I had connected it to the chassis before mounting the aftermarket radio but knocked it out when putting the deck back in. Replaced the wires and the new deck turns on and I can hear audio.

 

That said I have two more questions. First off, I don't have anything plugged into the antennae connector of the new radio as the one for my 94 is two pronged and I'll need to get an adaptor to fit it in the single pronged deck. Once I do that I'll get a radio signal, right? I only ask because I wired the 'amp turn on' wire on the new deck to the factory amp turn on wire in the car. I am unsure if that means its turning on an amplifier in the radio or the amp located in the rear of my car. Before I could get the deck to turn on, I wired it to the power antennae wire and when I would turn the car on I immediately would hear a motor (or something) turning in the right side of my dash or engine. This noise was common when I had the factory radio in as I would hear it every time I switched on the radio, I think it's the sound of the automatic antennae (though its never actually raised before). If I leave it hooked up to the amp turn on wire without anything connected to the power antennae, will I still get a signal or is that motor sound I'm hearing a necessary one?

 

The other question I have is that even with the new radio, I am still only hearing things out of one set of speakers. While setting things up I would hear sound come out of both the front and the back, though never at the same time. Before I installed the new radio it was very common for my audio to jump from front to back throughout the day especially in cooler (or maybe less humid) times of the year. I assumed that the problem was with the factory radio, but now I am starting to think the problem is originating from the amp in the back or even worse, the speakers. Does these symptoms tell you anything or would you need more information? I can post pictures if necessary.

[ahardb0dy]

I can't help you with the stock amps as I do not know about them or use them, With an aftermarket head unit I would advise to use an aftermarket amp (or amps),

 

The problem with no audio front to back or left to right sounds like the factory amp is the problem.

 

Yes with the antenna adapter you should receive an FM signal, does your truck have the antenna in the windshield? If so there should be 2 antenna connections behind the radio.

[PJMack]

Okay. I'll get an adaptor for my radio so I'll get a signal, thanks. As for the speakers, slartibartfast do the symptoms i described in my earlier post sound like something that bypassing the amp would fix? I saw your write-up on it I bet I could easily do that sometime this week.

[Slartibartfast]

I never had trouble with my amps (besides the fact that they were unnecessary and not designed to work with the new head unit), but it does sound like they're what's going wrong with yours. One amp does the fronts and one amp does the backs, so that would account for one or the other working (if it was side to side I'd be pointing at the head unit). I'm guessing there are a few cracked solder joints inside the amps, which makes them cut out when they're cold. The amp bypass should fix the issue.

 

The radio I installed had a wire for the power antenna, which I connected to the power antenna lead in the truck. (Got any wires left over?) It sounds like yours is broken. Mine was too. Some guys just ditch the power antenna and put a whippy one in its place. I fixed mine, because I kind of like the 90s novelty of the antenna popping out.

 

The amp turn on wire is how the head unit turns on the external amps. If you're bypassing the amps (and not installing other amps), that wire doesn't need to go to anything anymore. The head unit will run fine with it disconnected.

 

Also, you can rule out your speakers. If they were electrically dead (busted wire or something), they wouldn't come back on again. If they're mechanically busted (the foam between the cone and the frame dries out and crumbles), they'll sound lousy and make thumping noises as the cone thrashes around. My driver's door speaker did this shortly after I got the truck, and as a new driver, I immediately assumed that the tire was disintegrating.

Edited October 16, 2013 by Slartibartfast

[PJMack]

Thanks! I might consider fixing the power antennae, I'll need to deal with the amps first though. I have one last question, I feel like the answer shouldn't be hard to find out but I'm not having any luck. After I installed the radio, the lights to my dashboard and AC went out, and my clock can't keep an accurate time. I still get icons with their own bulbs, 4WD, oil, seatbelt, but all the meters won't light up when I switch on my headlights. I checked my radio/ac fuse down in the fuse box, as well as a few others but they all seemed ok. I read it also could have been the bulb under the dash for these lights burning out but I sincerely doubt they went out at the same time. My only guess is that I caused an imbalance in power when I wired the new radio, maybe I didn't find a good enough ground. I wired the ground to the metal wall on the left of radio around one of the holes that you screw in the deck with, however removing the ground wire obviously doesn't fix anything now. I'm assuming, unless you have a pathfinder exactly like mine, that description probably doesn't tell you anything. If anyone is still willing to offer advice and wants me to take a picture of where I wired my ground just let know, I'd greatly appreciate it.

[ahardb0dy]

just don't do what my neighbor did, this was driving him crazy, he installed a sony headunit and an amp in his old jeep and it worked fine when he played the radio but every time he switched to CD no sound, finally after he called me over I discovered he was using the power antenna wire hooked to the remote turn on for the amp and when you switch from radio to CD, the power antenna wire no longer has power going to it and it killed the amp.

[adamzan]

Did you check all the fuses and make sure you plugged anything you may have disconnected back in? Start with the simple stuff.

 

Some of the fuses are labeled retardedly like the meter fuse and the tail lamp one affect the dash lights.

Edited October 19, 2013 by adamzan

[PJMack]

Did you check all the fuses and make sure you plugged anything you may have disconnected back in? Start with the simple stuff.

 

Some of the fuses are labeled retardedly like the meter fuse and the tail lamp one affect the dash lights.

 

Wow, that was the problem. Why would the dash lights be connected to the tail lights? of course it had to happen right after I replaced the radio. Thanks for the help.

[adamzan]

I think the fuse is just not labeled that great.