No Power Through The 12v Power Wire For Audio Connection

[es30031]

Hello all,

I have a '98 es300.

I recently installed an aftermarket deck and everything worked fine. I then went to take out some peripherals and removed some connections from the 12v, always on cord. I t-tapped about 4 connections to the 12v wire, and removed all but 1, meaning only 1 is t-tapped to the 12v wire, currently. I go to power up the deck and nothing. I checked both radio fuses and replaced both of them and still no power. I checked that everything is properly grounded as well. I also t-tapped the 12v ignition wire to use a radar detector and the radar detector works when I turn the ignition on. I try the radar detector into the 12v always on t-tap, and no power.

Does anyone have any idea why I don't get any power through the 12v wire? Thanks.

[blk_on_blk]

I'd have to see exactly what you connected/disconnected to know for sure, but when I did my install, I was told part of the wiring was for a hands-free system integrated into the vehicle. When I disconnected some of the peripherals, I lost connections to speakers and other oddities.

For me, the topic would be moot, because it's always best practice to run a clean, heavy gauge power wire from the battery when installing an aftermarket head unit. The aftermarket head units have a much more powerful internal amp and draw much more power as a whole. Who knows what the load rating is on the always-on power lead, and who knows what else it feeds and/or where that power is pulled from. Plus you will get a more 'clean' line with a hard-wire to the battery (which cleans out a lot of the alternator interference). Lastly, you will also have a clean, heavy line to power any other 12V device you want to bring into your vehicle (the radar detector, heated seat covers, or other). Just be sure to fuse the new power lead at the battery in case it shorts out somewhere.

[es30031]

Ok, so I took your advice and did that. I have 2 questions now, I used 14 gauge wire and am having a real difficult time finding a ring terminal that will fit around the + end of the battery. Any idea what I could do? Secondly, do I need to ground a cable from the negative terminal to the chasis of the car? Thanks again.

[blk_on_blk]

You don't need to necessarily fit it around the terminal itself. You can tie into the battery cable at one of the fastener locations (i.e., the clamping bolt that squeezes the terminal). If you have an alternate style of battery terminal (the screw in type), then you strip the insulation off the 14 gauge wire, loop it big enough to fit the terminal properly, then solder/tin the whole loop to get it rigid and sealed. I would use some contact grease/paste when connecting to the battery, though, for that's an exposed area with lots of engine heat and a spot for potential corrosion... a little contact grease/paste will seal out moisture and help protect it.

On your second question, no, you do not need to run the negative side of the body to the chassis of the vehicle. The battery already grounds to the engine block and/or the frame, so just get a good clean spot on a key piece of the vehicle's body metal, or better yet the factory ground, and that should work well. It's the positive lead that is the critical one. I mean, don't get me wrong, you want a clean ground, but the factory location should be clean.

Lastly, don't forget to run a fuse right at the connection to the battery. That way if anything shorts out, you won't have any issues.