Subaru Outback Forums banner

1 - 20 of 41 Posts

·
Registered
2003 Subaru Outback 2005 Ford Ranger
Joined
·
350 Posts
Discussion Starter #1
I was parked against a building tonight at work. After I started my car I was sitting there for a few minutes and turned on my lights and got ready to leave. Well, I put the car in reverse, started to release the parking brake and as I put my foot on the brake, my headlights dimmed. So i pushed the brakes again and the lights dimmed again. Is this normal? Never noticed this before.
 

·
Registered
Formerly 04 Outback 3.0R VDC, now 2011 Mitsubishi Pajero GLS DiD
Joined
·
1,617 Posts
I can't say I've noticed on the Outback, but if the engine is just idling when it happens it kinda makes sense, most cars don't generator enough electricty to run everything at idle speed so actually drain the battery with the main headlights on, adding the brake lights I guess is getting a bit much and making a noticeable difference. It could also mean your battery isn't in very good shape I suspect.
 

·
Superb Moderator, ,
MY12 WRX, MY07 FXT
Joined
·
6,186 Posts
That's somewhat normal, depending on what other current draws you had at that time (defroster, blower fan...) You could always check your voltage across the battery under a load to make sure it's not dropping to much. Brian
 

·
Registered
2003 Subaru Outback 2005 Ford Ranger
Joined
·
350 Posts
Discussion Starter #4
I didn't have anything else running at the time. The radio wasn't even on. My battery has performed fine all winter. I tried this in my girlfriends Accord and her lights didn't budge. Thought maybe it was a Subaru quirk...
 

·
Registered
Joined
·
50 Posts
Actually, I've noticed that same thing in my 1989 ford probe and my mom's taurus. I think it's normal when lighting up atleast 3 extra lightbulbs. Most cars don't have very heavy duty electrical systems. I did notice though, after intalling a sub with a one farad capacitor, the lights in the outback don't do it as badly.


Enouen
 

·
Registered
2002 OBW
Joined
·
2 Posts
I noticed the same behaviour on my '02 OBW. I just bought the car and the bumper-bumper warranty ends in about a month. I'm having the electrical system checked over by the dealer while it's still covered. This does not seem normal for a car that is loaded with electrical options (heated seats, wiper/mirror defrost, etc). I love this car and it's the only thing I could find wrong with it. I will add more info to this thread after the check-up.
 

·
Registered
02 OB sport, 2.5, 5MT, WRX seats/catback/rear bar, Hellas, Home Despot CAI and roof rack
Joined
·
1,572 Posts
injektilo--

i don't think this is normal or a design issue. even at idle, your alt shd be able to put out enough amperage to run all the stuff you had going. even if it isn't, as Jondalar correctly noted, a good battery shd be able to handle those loads without lights dimming.

dimming lights when another load is added to the system often indicate either a battery that doesn't have enough reserve capacity to handle the loads, due to age and attrition, or a bad ground somewhere. first thing i'd check is batt voltage at idle under max load (ie, all lights and accessories on). if you still show 13 volts plus, your alternator is OK and batt probably is too. next, look at ground connections. your battery terminal connections ARE clean and corrosion free, right? check the end where ground cable connects to engine block.

it could well be something else, but these are the real basics i'd try to eliminate before going on to look for more exotic sources of problems.
 

·
Registered
02 OB sport, 2.5, 5MT, WRX seats/catback/rear bar, Hellas, Home Despot CAI and roof rack
Joined
·
1,572 Posts
i just checked your profile. if your 2001 car is still on orig battery, this may well be your problem. also, they do salt roads up there? this plays havoc not just with bodywork and mechanical connections, but also with electrical ground points to body.

if you temporarily add a heavy (6-8 gauge or heavier) aux ground wire between your batt neg terminal and good engine block ground and problem goes away, it was certainly bad ground. add the aux ground wire permanently if so.
 

·
Registered
2003 Subaru Outback 2005 Ford Ranger
Joined
·
350 Posts
Discussion Starter #9
Thanks for the response guys. I'll look into the battery and see what I find. I bought the car used but am willing to bet the battery is original.

Hopefully it's not a more exotic issue.:D
 

·
Registered
Joined
·
181 Posts
I could never brake at night in my X1/9. Or I would have no idea where I was heading. :D Not only at idle either....I replaced voltage regulator, battery, even the alternator, but that never went away.
 

·
Registered
02 OB sport, 2.5, 5MT, WRX seats/catback/rear bar, Hellas, Home Despot CAI and roof rack
Joined
·
1,572 Posts
after thinking abt it more, if you are on orig battery, i'd almost certainly bet it's the problem. stuff like Optimas and clones thereof aside, i've simply never seen a battery that lives for its rated life expectancy, and essentially none for more than abt 4 yrs.

the "plates" you hear referred to are actually more of a lead "grid" sort of like a coarse screen, which hang down into the electrolyte. these eventually hit each other and short out, i suspect partially because they're able to move slightly (lead does NOT flex well...)

observation on battery marketing economics: the battery that dies before the # of months on the top is of course covered by warranty. the warranty provides for a pro rata credit toward another one of the same seller's batteries; of course, you get to pay the balance. if the seller simply puts a higher # of months on the top than it will actually last for, they can generate LOTS of repeat business.....:(

for next batt i get, i'm going to try an Optima or similar where the "plates" are prevented from moving by spiral core mat or gelled electrolyte. FWIW, the orig battery on my 02 OBS died at abt 38K and 2 1/2 yrs. :eek:
 

·
Tokyo's between my toes
2001 Wintergreen Outback 5MT
Joined
·
6,684 Posts
Excuse me, I'd like to respond to this thread but I have to jump my OB that has been sitting idle...
 

·
Registered
02 OB sport, 2.5, 5MT, WRX seats/catback/rear bar, Hellas, Home Despot CAI and roof rack
Joined
·
1,572 Posts
down here, they think jump starting will cure anything...maybe it will fix leaky head gaskets....??
 

·
Tokyo's between my toes
2001 Wintergreen Outback 5MT
Joined
·
6,684 Posts
So I did jump it off the Buick, felt good to drive it again.

I wanted to do that yesterday, as the temps dropped 30 degrees overnight here. We have a thin layer of snow on the patio table this morning.

Now, will it be able to start itself in the cold today..?
 

·
Registered
02 OB sport, 2.5, 5MT, WRX seats/catback/rear bar, Hellas, Home Despot CAI and roof rack
Joined
·
1,572 Posts
when i read that first sentence, i had evel Kneivel-esque visions involving a ramp over the Buick....:eek:

wow, i didn't know it still went. if you haven't had anyinternal dmg yet, have you considered the o[ption of going to sheet copper head gaskets? PAECO in B'ham Ala (racing shop popular with SCCAers, in biz for years with good rep) custom makes em for any vehicle if you send em uncompressed stock head gasket and $2-300ish. these will seal almost anything and are popuilar in mile-high compression ratio and forced aspiration situ.s might be cheaper than $2500.

how do the crate engine rebuilding folks make their head gaskets seal anyway, if it's an inherent design flaw? not trying to be facetious, it would be useful to know....:8:
 

·
Tokyo's between my toes
2001 Wintergreen Outback 5MT
Joined
·
6,684 Posts
The head gaskets have been re-designed at least four times (hmmmm...) and when I turn this one in I want to specify the correct part number of the newest version.

Yes the engine runs but it blows so much oil that it smokes off the pipes when I run it. I bought a fire extinguisher for it.

After some of the grounding kit discussions, I want to install some better grounding leads, that should be an easy thing to fabricate myself.
 

·
Registered
02 OB sport, 2.5, 5MT, WRX seats/catback/rear bar, Hellas, Home Despot CAI and roof rack
Joined
·
1,572 Posts
aux ground leads are ALWAYS a good idea to install, even if you're not dealing with an old Brit or German vehicle. no, there's no magic to any of the kits. except if you need color matching engine bay. just make sure your aux ground wire is heavy enough (#4-6 cable or heavier, with end lugs crimped/soldered on like welding cable). you can NEVER have too good a ground setup. as a side benefit, it will help keep your gauges from acting weird if your main ground develops some corrosion.

since a voltage reg essentially acts as a LIMITER on system voltage....the alt can produce more than enough juice to run all accessories and charge the batt if it's working correctly, and the voltage reg acts like the shutoff valve in a toilet tank to prevent alt. from overfilling (frying) battery.....i'm a little skeptical about a voltage regulator device improving power and all those other good effects. am i missing something??
 

·
Registered
2007 outback MT
Joined
·
135 Posts
I noticed my lights dimming as i applied the brakes today. Could it have something to do with the 1000 watt stereo system i have installed? Or should the alternator and battery be able to accomidate this?
 

·
Registered
2007 outback MT
Joined
·
135 Posts
I noticed my lights dimming as i applied the brakes today. Could it have something to do with the 1000 watt stereo system i have installed? Or should the alternator and battery be able to accomidate this?
 

·
Registered
2004 Subaru Legacy Sedan 35th Anniv. Ed
Joined
·
82 Posts
I've seen the exact same behavior -- dimming lights when I hit the brakes at night -- on both my '04 Legacy and mother's '02 Outback. Both vehicles have done it since brand-spanking new.

If you really want to see / hear something weird, start the car during a cold night, turn on your windshield defroster full blast, turn on headlights and fog lights, and hit your 4-way flashers. Get out of the car and walk around to the back. I have heard on both cars the fuel pump actually pulsing, and can see the tail lights dimming in time with the 4-way flashers.

Seems to me that Subaru skimped a little bit on the alternators, putting in the lowest possible amperage. Probably for two reasons: cost and fuel economy. Turning a little alternator at 700 rpm just doesn't put out enough power to give everything maximum juice... but turning a big alternator at any RPM will take more power, which will rob power from the actual driving of the car, and will also eat more gas.

When the alternator in either of these cars breaks, they'll be replaced with something much beefier. However since both cars are bone-stock (for the moment :D ) I won't mess with it.

In regards to aftermarket stereos, etc... that's a whole new ballgame. The shop that installed the stereo should be able to give you advice on sizing an electrical system to your needs.
 
1 - 20 of 41 Posts
Top