I’m trying to install a mobile radio in the aforementioned vehicle. The instructions say to hook it up directly to the battery and run the cable through the firewall. This has been rejected because of what you might call non-technical reasons. I’m going with a fuse tap with a fuse for an accessory that my car doesn’t have. I have spent a lot of time watching YouTube videos on how to install the fuse tap and how to hook it up to the positive side of the radio’s cable. I’m crystal-clear on that point. I am also crystal-clear that the black lead goes to ground - that is to say, the chassis.
My question is this. Where, exactly, should I hook up the black lead? And before you reply with “LMGTFY”, I have Googled and found nothing more than a bunch of rice boys arguing over whether using a grounding kit works or not.
Is this a business or ham radio or are you adding subs and amplifiers for sonic showdowns?
For a replacement AM/FM dash radio there are connector kits from Scosche and others that allow you to plug into the existing wiring which includes ground.
For a ham-type radio there are power tap wire attachments that can be plugged into the interior fuse block. Or any bare metal that’s part of the body structure can be used for ground. You could use an ohmmeter (voltmeter) to determine that a metal surface is the same potential as the ground side of the battery.
If you’re going for a high power thumper setup you probably need a professional stereo installler.
Virtually any metal part of the body can serve as a ground point, as can anything metal attached to the body, e.g. steering column, pedal bracket, etc. Typically one would drill a hole in a convenient panel and use a sheet metal screw, or use an existing bolt that’s holding something. The ground wire should have a ring terminal of appropriate size for the screw or bolt.
As a former 2003 Accord owner, I would suggest that you run it through the tube that connects the door to the dashboard (and holds the wiring for the side mirror). There should be any number of screws in the door/window assembly you can attach the ring terminal to without having to drill a hole for a new one.
Pretty much this, and it’s worth noting that there are other grounds besides chassis ground in your car and not all grounds are the same. Some sensors use a signal ground that is noisier than chassis ground. So, don’t necessarily splice into what you think is an existing ground wire. Rather follow Gary’s instruction above.
As a bit of a followup - I installed a new radio in my daughter’s 90’s Camry a month ago. The RADIO instructions had that exact statement of using a ground connection but the stock radio was not mounted to anything grounded nor did it have a ground wire. All the pigtailed wires to the radio itself were to one connector - no “ground” wire. The new radio wire harness had a black ground wire and the Scosche adapter kit showed the ground connection of the Toyota wiring. I connected the wires as marked, plugged it together, and it works great!
While grounding the body of a radio to the car chassis may provide a degree of static shielding or guaranteed ground, one almost certainly knows that the original plug connectors provide all the connections the radio needs. Manufacturing would NOT depend on clean dashboard metal and sheet metal screws to put a new car together.
One thing that can work if the interior is completely swathed in plastic is the cigarette lighter port. Sometimes if you pull them out, they even have extra blade terminals on the grounded outer housing thing.
Are you sure about that? Where does the original radio connector get its ground? Have you traced it out? I know VW & Audi often get their grounds this way. Sometimes they use the firewall, but often they use the dashboard.
Welp, the 12-gauge lead didn’t fit into the fuse tap, so we hooked up the leads to the battery and called it a day. I still need to find a point to attach the black lead, but I think it’s fine where it is for right now.
Unfortunately, the antenna I bought to go with the radio has to be frequency matched and analyzed. I’m trying to borrow another one until I can get one of my own. :mad:
OK, Now you have me curious. #1. Yes, but where do the two body wiring harness plugs get their grounds?
It could be through an eyelet or a connector that hooks to the Negative battery cable, or it could be from a welded terminal on the body some where, or it could be from a bolt that goes through a hole in the firewall/ fender/ dash board support.
A VW Rabbit that I worked on had a multiple male spade connector attached to the dash support with what looked like a sheet metal screw. It had many wires from the wiring harness connected to it. Thus, it supplied the ground for many items. As it was not loose & it passed the ohm test, I did not mess with it. The intermittent problem was in the wiring harness itself. Man was that hard to find!
I will give you that the entire harness, or the two body wiring harness plugs, probably do not use sheet metal screws in their grounding circuit. What year & model Toyota are we talking about here? I can probably look it up from that info.
Never mind, I must be bored out of my gourd to ask this anyway.
