Aftermarket Radio Installation: 12v constant, memory, etc...

I have a 2002 Dodge Durango. I bought an aftermarket Pioneer DEH X181, or something like that.

Everything is dandy on it, except that I can’t get it to retain memory. I connected the yellow 12v constant wire to the red power wires (I’m using a Scosche harness adapter). When I turn the vehicle off for a second, then back on, the radio retains memory. When I turn the vehicle off, then go into the house for an hour or more, the memory disappears.

I went online, and read to try hooking up the red power with the yellow and visa versa, in case the factory criss-crossed them (Pioneer says that this sometimes happens). Also, to get the radio out of Demo mode. I think that I followed these instructions correctly, and got no result.

So, currently, I have the red from the adapter hooked to the red from the radio, which gives me power, and I have the yellow memory wire connected to them. I have previously had the orange wire, from the adapter, as well as the yellow wire from the adapter twisted together with the 2 red and 1 yellow memory, and it still didn’t work.

BTW, I am at a total loss when it comes to electronics. I read on one forum about busses, then I realized that I was getting off into that other world. All I know is if you hook up X wire with Y wire, and power comes on it is good, and if it blows a fuse, it’s bad.
I have hooked probably 5 stereos up using Scosche harnesses, but, I haven’t come across this problem before, as following the instructions always seemed to work.
At this point, I’m wondering if there is just some constant wire that I can (easily) hook my yellow constant wire (from the radio) into. Can anybody here help me?


Use your multimeter to identify which wire from the truck is a constant 12 volt source and which is a switched 12 volt source. Memory lead goes to the constant 12 volt source.

Second using your meter to determine which wire remains hot.

Or go with what you have and call it a Memento Radio, since the movie is being remade?

With out the meter, hook both (hot) input to the constant 12V source. You should be able to play the radio now without the key in the ignition. If not you don’t have a 12V constant source.

Also it is possible that some lines get unpowered only during starting the car, so with the above crank the engine, if the radio goes off you don’t have a 12V constant source. For a short time the capacitors in the radio may keep the memory alive, such as the engine is already hot, so it doesn’t crank long, but sitting overnight you may have to crank it longer to get it started and the radio loses power long enough to lose memory.

For that matter perhaps your battery drops too low during cranking, again overnight = longer cranking time, and loses memory there.

nope, wrong. why would you do that? You’re supposed to connect the wires from the aftermarket radio to he same color wires on the Scosche adapter. That’s why the aftermarket industry settled on that particular wire color scheme (yellow=battery, red=switched 12V, blue=power antenna, etc.)

And the bigger problem is that the constant (battery) circuit (yellow wire) is not only for the radio’s memory, it’s also the circuit it draws all of its operating power from. The red (switched) wire is nothing more than a sense lead, and doesn’t draw more than a handful of milliamps. You are not supposed to power the radio via the switched 12V wire, especially since it’s probably on a circuit with a much lower rated fuse.

For years I wondered why the radio manufacturers don’t spend 25 cents for a serial eeprom chip.

What would you do with it?

Thanks, guys, for all the info.

I’ll grab the multi and check it out!

Thanks, again!

Presumably because if the battery is dead, you have bigger problems than the radio forgetting what station you were listening to.

The car manufacturer specifies what features they want in the various pieces of electronics that go into the car at the factory. The radio doesn’t need non-volatile memory. The odometer does (for digital odometers). As do things like the throttle body adaptation value.