Hello everyone, I did a ton of searching about my intermittent no start issue on my 2007 forester sports 2.5 non turbo. I didn't find anyone who's car won't start sometimes and when it does, after 4 seconds holding the key. Starter switch low input is what's said about the code however it makes no sense to me. The battery is new, the starter sounds ok and what's even stranger is that if I hold my key to the on position, it won't do anything for about 4 seconds and then if I'm lucky, it turns over and starts like nothing is wrong. It runs smooth, and the starter solenoid doesn't sound like it's sticking open. If I clear the code, it goes away for 150 miles and comes right back stranding me (if I'm not lucky and it doesn't turn over after 4 seconds holding the key).. Gas cap is also verified to be in proper working order.

 

I don't have the money to go to the dealership, no warranty, bought the car about 4 months ago,I have good mechanical aptitude. I am more into Diesel engine swaps and jeeps, and newer cars like this are confusing for me. Can anyone point me in the right direction?

Welcome to the USMB, Cmine.

 

Do you hear the solenoid click every time--whether the starter cranks or not?  Could it be pitted/burnt contacts in the solenoid (the heavy duty ones that feed juice to the starter motor)?  That's a common problem in older EJ engines.

Well, forget what I said above!  That wouldn't throw the code you're getting.  I found an old discussion about P1518--don't know if it sheds any light or not!

 

http://www.ultimatesubaru.org/forum/topic/81077-cel-p1518-starter-switch-circuit-low-input/

The starter clicks and absolutely nothing is out of the norm as far as sounds or starting "feel". Only thing is 80% of the time it won't start, and the remaining time it will start normally if the key is held on for 4 seconds.

 

I have an abnormally long commute to work this week and can't get stranded... Tomorrow I'm going to check the starter solenoid connection, anything in particular I should look for?

 

Thanks a lot for the response

seems to me, there's a likelihood of a corroded connection somewhere. Bad ground?  When were the batt terminals last cleaned? Has there been a history of corrosion on top of previous batteries? that can grow into battery cables. (though, your cables seem too new to be bad - I suppose it's possible.)

 

that 4 seconds feels like it could be due to current trying to punch thru some salts or corrosion. Checking some voltages/voltage drops during cranking might be a good idea,

Edited October 28, 201411 yr by 1 Lucky Texan