[rgutter]

I installed a new battery on my 2006 Outback Ltd 2.5i (4AT NA) . All voltages checked ok with ignition ON under load, but 1st time I turned to START I got not a click but more of a thud, and then all DC shut off. No dash, no dome, no alarm, no door chime.

Key out, back in, back to ON. All still dark and quiet.

Post to post still read 12.6V, as did positive to solenoid or other grounds. All the obvious under the hood fuses seemed good.

I went back to the car, as as soon as I opened the door it chimed. Sure enough, I’d left the key in and ignition ON, and now the dash is lit up etc.

Had I jostled something back into place? Reseated a fuse or relay that was a bit loose? Seemed unlikely, but maybe.. So I turned the key to START. Thud, and power disappears again.

I went through three more cycles - no power/connections etc. check out ok/return ignition to ON & power’s back/try to START & power shuts off). I tried to be gentle and NOT confound the testing by moving wires. So maybe the temporary power restoration was just due to the time it took to check things out?

On the fourth attempt, the starter kicked in and everything purred like it should. No problems for two days now. Also, once I got it running I saw that the clock – which had reset when I changed the battery – had kept time throughout the process.

I'm thinking that before I worry about the ignition switch, solenoid or starter it might be best to check the starter and security relays. I’d certainly appreciate anyone here who'd like to offer up an opinion/idea/suggestion. Thanks.

 

[eagleeye]

miles?

 

[rasterman]

You've got a bad connection somewhere. It's good enough that the tiniest of vibrations is letting it reset and pass a small amount of electricity. Enough to kick a meter, heat up a dome light, ding a seatbelt dinger etc. When you attempt to start, the bad connection arcs (sparks) and vaporizes a small amount of material. The gas and air leaving that arc flash area pushes the connectors further apart, resulting in electrical blackout. Then you get out, move stuff around etc and the connection resets itself (barely) and the cycle is ready to repeat.

Find the bad connection and make it good again. Usually it's the battery terminals themselves, sometimes it's the "sandwich stack" outer edge of the + connector. Sometimes it's the cable itself, and sometimes it's the connector on the starter-end of the cable.

Clean the terminals with wire brushes, abrasives etc until you have shiny metal. Remove chalky deposits from the battery posts.

When you seat the battery cables, make sure you open them enough to make room, tap them down onto the posts with a tool until they seem tight, then tighten the clamp. The posts are slightly tapered.

 

[1 Lucky Texan]

what were the symptoms with the old battery?

have you used the fob to cycle the security systems on/off a coupla times?

 

[dukey33]

Loose battery cable.
Tight enough to provide power at low current levels but arcs out when the starter is engaged.
It can intermittently provide a good enough connection to give starts, but one day will give you fits again.

Clean and tight.
Check all your connections are clean and tight at both ends of both battery cables.

 

[johnre]

If these are the original battery cables, they are now old enough that they could be internally corroded. Changing the battery could have flexed things enough that it's now intermittent.

Slice open the insulation a bit and tale a look - if it's OK, just tape it shut again. If corroded, replace them both.

 

[rgutter]

Thanks to all for the quick responses and advice!
@eagleeye: Only 35K (really).
@1 Lucky Texan: Good question! (I hadn't wanted to bore everyone with the preamble.) I replaced the battery because I had 3 no-starts over the last 3-4 months. Car wouldn't start, but it was a "normal" failure - just the click-click-click that most likely spells starter or lack of juice into starter. Would boost instantly, and after driving even a block the battery voltage was fine and car restarted. I suspected a parasitic drain, but by the time I got to checking it out the 3 year-old battery wan't holding a full charge. Of course, that could have been the problem all along. Either way, it had to be replaced. As for the fob, I had assumed nothing would respond; but if/when the power dies again I'll give that a try.
@rasterman: All the cables and connections were checked even before I switched the batteries (as above). The posts are of course new, but you're right I should give them a buff and recheck the post-to-cable connections. And note that even before I tried to start it the first time with the new battery I checked things out under load (lights, blower, radio) and saw (post-post) 11.89v. Key off immediately returned to 12.43v, rising to 12.55v within a minute, at which point I tried that first start.
@dukey33: Yup, will re-check.
@johnre: Already done.

I'll let you all know what I find...

 

[eagleeye]

ultra low miles can mean lots and lots of starts.

like what if the person who owned it before lived 2 miles from the train station. = over a 5 day work week: 10 starts, 20 miles.