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Coastal Electronic Technologies 12V batt charge - Lighter mod?

Discussion in 'Gen 2 Prius Accessories & Modifications' started by HiJoe, Apr 28, 2022.

  1. HiJoe

    HiJoe Junior Member

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    I'm going to put my 2009 Prius into storage for several months, and while I have someone coming to drive the car for 20 minutes every 3 weeks, I want to be sure the 12V batter is charged when they come over.

    I'm going to use an external solar charger on the outside of the car cover (planning on "Omeisivn solar 30 Watt 12V Lead-Acid Battery Charger Trickle Charger").

    Rather than have the guy who will be driving my car connect and disconnect leads from the battery, I wanted to have a simple plug into the dash lighter.

    I understand that "Coastal Electronic Technologies" used to make a simple kit to be able to charge the car when off. (page is still up but the product not available 4/28/2022)

    I called them and they had a merger and apparently retained their name, but don't make that product anymore.

    Any idea if someone else makes a very simple conversion kit like they used to?

    -H
     
  2. ChapmanF

    ChapmanF Senior Member

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    Looks like their 'kit' was nothing more than a bit of wire and two insulation-displacement wire taps, with instructions telling you to jump it between the light-green wire (1K pin 2) at the fuse box and the white wire at the front power outlet. So it simply jumps around the power outlet relay.

    A simple-enough mod, because that relay serves only the front power outlet, so you can jump around it without powering up all the car's other ACC-mode gizmos.

    I would have thought it faster to just pull out that relay, pop its cover off, wire the contacts together ;), and plug it back in. But it's located inconveniently beneath the dash top, way up by the driver's A pillar.
     
  3. dolj

    dolj Senior Member

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    Why not just buy a plug and socket, some wire eyelets, and some wire and just make your own "quick connect" that you can attach directly to the 12 V battery in the back? You then feed the plug up through the rear light access panel onto the floor of the hatch. Your guy can then just disconnect it there before driving and then reconnect it after the drive.
     
    #3 dolj, Apr 28, 2022
    Last edited: Apr 29, 2022
  4. Another

    Another Senior Member

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    You may want to look at this simpler solution from a well known company. It uses the always on OBD Dara port
    Battery Tender 5 Watt 12 Volt Solar Panel Charger and Maintainer with Charge Controller, IP67 Weatherproof, Includes Windshield and Handlebar Mounts, Ring Terminal Cable and ODBII Connector
     
    HiJoe likes this.
  5. HiJoe

    HiJoe Junior Member

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    Hi Another, I would prefer a known solution. However, I understood from different posts, I might want to keep the wattage higher than 5W to keep the battery active. Will 5W do the trick? It will be driven once every 3 weeks or so for about 15 mins.

    Other who replied to my post, should I try to just go through the ODBII port as a better solution to the cigarette lighter approach?

    If so, I can focus my solar panel search to ones that connect there and forget about the mod.

    -H
     
  6. Another

    Another Senior Member

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    I’ve read other posts that say 5w is not sufficient
    That may or may not be the case if your car is in the shade.
    These panels work well for parking cars for weeks at a time in airport parking lots which is how I came across them.
    Not my place nor desire to tell you what to do. Only responded to your request for alternatives. You can call Battery Tender and talk to them to answer your questions. They are a well known vendor who have been in business for many years.
     
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  7. Another

    Another Senior Member

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    I forgot to mention that Battery Tender also offers higher wattage solar panel chargers.