Retained Accessory Power
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Modern cars have a feature called "retained accessory power" where the accessory power stays on with the key turned off until a door is opened. Some are even smarter and restrict it to the drivers door being opened. This allows you to pull up to a store, turn off the car, let the rear passengers out - and maybe even the front passenger - and still listen to the radio, etc. Most cars also include a timer that shuts off the accessory power after some time period - 10, 15, and 20 minutes are common times used on various cars. It's one of those little "nice to have" things that make modern cars nicer and more enjoyable. Adding this feature to older cars is pretty straightforward once you know how.

If this concept seems odd to you or you have no idea what I'm talking about, then search Google for "retained accessory power" and start reading.


The Aftermarket Solution

Dakota Digital offers this as part number PAC-1100 for $74.95. They offer part number PAC-1200 for $124.95 which also adds control of the dome light - both a time delay to turn it off and a smooth fade out when it does turn off. Their top-of-the-line version is part number PAC-1300 for $199.95. which does everything that the PAC-1200 does plus automatic headlight control. Other companies may offer similar control boxes, but I have not found them, so shop around to see what's out there.


Custom Solutions

While researching this page, I found a good website with all manner of interesting relay-driven solutions to various wiring problems, including adding retained accessory power. Check out and scroll down to the "retained accessory power" section. Browse around the site to see the other ideas they have.

Comments? Kudos? Got some parts you'd like to buy/sell/barter/swap? Nasty comments about my web page so far? You can email Mike or Debbie.

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Page last updated 01/02/2009 01:51:39 PM