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my outback has a voltage drain that causes my battery to go dead. took the negative cable off and put a test light to it and there is a pulsing light does anyone know if this is normal?
 

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Year, engine, transmission?

Is there a pulsing light with the ignition key out? How rapidly does it flash?

Does your car have the "security" light in the instrument panel that flashes periodically?

Any non-original accessories/options added (stereos, etc)?

"Dark current", that is, the drain on the battery when the car is off, shouldn't be more than 150 mA (0.15 Amps). Do you have a meter to check the current drain?
 

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I have the EXACT same issue. However, if I remove fuse #12 from the engine compartment, the light goes out. That fuse is labeled Interior lights & clock. However, when it's pulled the radio is also "dead."

I removed every interior light in the vehicle and the light was still pulsating. This tells me that it's not in the lights. This leaves the clock. However, it's hard for me to believe that the clock would draw that much power.

Any and all help would be very much appreacited.

2002 Subaru Outback. 2.5L
 

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if I remove fuse #12 from the engine compartment, the light goes out.
Fuse #12? Are you sure that's the number? My 2002 wiring diagram shows only 9 smaller, blade-type fuses in the engine compartment fuse box. Is it one of the small fuses, or one of the larger, slow blow fuses?

If we can identify the fuse, then that might narrow down the related circuits (provided there's no aftermarket stuff or modifications, as subiesailor mentioned.)
 

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I just double checked, and yes, it's the 15A fuse, #12 in the engine compartment. This is oneof the smaller blade type fuses. There is no after market stuff in the car. The thing that has me stumped is why the radio is off when that fuse is labeled only for interior lights and clock?
 

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The thing that has me stumped is why the radio is off when that fuse is labeled only for interior lights and clock?
While I can't verify it on the wiring diagrams, that fuse probably provides the "always on" power to those devices. Both the clock and the interior lights (for example the ceiling light) continue to work when the key is out. The clock display might go off, but it's still keeping time.

Looking back from the wiring for the interior lights, Fuse #2 (15 Amps) in the diagrams seems to be the one. It provides "always on" power to the

Luggage room light
Room light
Security control module
Security horn relay
Spot light
Step light
Trunk room light
Auto A/C control module
Combination meter
Radio
 

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Thanks for the speedy replies. In my owner manual, all I see is "Interior Lights" and "Clock." Where do you see the radio listed? I totally agree, by the way, that it must control that item, but curious to know your source.

A few years ago when this issue first started to come to happen, we jammed a CD into the CD player. Do you suppose that the player is just sitting there trying to play or eject that CD?!?!?!! Could this be the issue all this time?

Also, of the components you mention, which do you think would consume power in that oscillating manner reflected in my test light?
 

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The list is from the wiring diagram set I have for 2002.

I don't know if the CD player could be a factor. I guess one way to find out would be to pull the connector on the back of the radio and see if the pulsing stops.

The assumption being made is that the flashing reflects something that is turning on and off when it should not be on at all. But it's also possible that it's normal. Instead of the test light, I'd prefer to have an actual reading of the dark current level. Because a pulsing light includes the "off" time (i.e. no current), it doesn't clearly reflect the average dark current, which could be within the 150 mA limit. (In other words, what you're seeing with a test light might be normal.) Measuring the drain with a meter would be more reliable. A clamp-on meter is easiest -- doesn't require disconnecting the battery -- but most digital multi-meters can measure DC current in the range of interest.
 

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About 3.5 amps
Ouch! At that rate, a fully charged battery would be run down overnight. How have you kept using the car for the past few years?

The pulsing is strange.

Do you have a sense of the rate of the pulsing (time on, time off)? Is it anything like the rate when the Hazard lights are switched on? Is there any "clicking" under the dash?

Isolating the problem might have to be a process of elimination, perhaps starting with the radio. It might be continuously trying, stopping, and trying again, to run/eject the CD.

With the exception of the two control modules (perhaps only one if the car does not have the Auto AC) and the combination meter, the other circuits are light bulbs that could be pulled to exclude them, but they're not likely to be turning on and off.
 

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Hi, No clicking under the dash, and I'd say it's 2 cycles/second--pretty fast. I gave up trying to solve it myself. Documented what I know so far and took it to a shop. I'll let you know what it turns out to be.
 
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