chrysler radio drains battery?

Older radios use a bit of current to keep memory of station pre-selects alive, that small amount will eventually drain the battery, I hope newer ones have non-volatile memory.

Your message isn't coherent on when the problem occurs. You need to parse into sentences and check for contradictions before posting.

Draining the battery when running would indicate the charging system is not working - the ignition will drain the battery faster than a radio will. (Unless someone installed a monster sound system, in which case I would refuse to help the owner.)


The speakers are only energized when the ignition is in Accessory (for those vehicles that power the radio then) or Run.

I don't accep the mechanic's claim, he does not understand radio systems.

Perhaps the radio is staying on - check that it is off when the ignition switch is in the OFF position. Worn ignition switch mechanism could keep it powered.

The mechanic is not a very good mechanic, as far as diagnostic skills.

Procedure: Measure the current draw on the battery, and its open-circuit voltage, with and without fuse installed, with engine off. Then measure battery voltage at idle. Current draw when off should be about 30mA or so. Battery should be about 12.5V with engine off, and 14V at idle. Radios only draw about 1mA or less of current for backup power, and typically only a couple of amps when running. So if running the car with the radio fuse installed can pull the battery down, it's NOT the radio.

Often there are other circuits on the radio fuse, such as the dome light, glove box light, or even one of the computers.

So the thing to do after the above steps is to leave the fuse in, but unplug the radio, and measure the current draw again. I'll bet unplugging the radio makes no difference. The mechanic needs to find out every circuit that is powered off that fuse, and unplug each device one at a time until the current draw drops. That will indicate what's really at fault.

In many newer vehicles, the radio and other electrical accessories can be kept on for selectable periods after the ign key is turned off and until a door opens. This feature is controlled by the TIPM, CCN (cluster) or BCM. Battery power is always at the radio and the radio is switched on and off by communications bus logic commands. This could be problematic with an aftermarket radio.
The station presets in a Chrysler radio have been non-volatile since 1996, meaning that they will stay in memory after a battery disconnect. The clock is dependent on battery memory and has to be reset.
Display and faceplate illumination dimming may also be PWM (pulse width modulated like a fuel injector) by a driver in the CCN or BCM over the communications bus.
Nothing is simple any more.
You need to see how the radio has been wired in and if the radio may be made compatible with an interface. The installer may not have had the know-how or materials:
http://www.discountc...m/RP4-CH11.html
or
http://www.discountc...m/C2R-CHY4.html