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05 outback dead battery, no start. Help

21251 Views 30 Replies 10 Participants Last post by  klausc
Hello All,

New to the forum. I'm usually on the jeep forums with my TJ but i have a problem i can't seem to figure out by myself. My wife has a 2005 Outback 2.5 SOHC auto. On Sunday i was cleaning her car out and getting it it ready for winter(blanket, water bottles, hand warmers, shovel, etc, etc.). I had the rear hatch open for no longer then 20 minutes. I happen to notice to cargo light was a bit dim and i suspected the battery was probably dead (I have noticed the car takes a little more effort to start the past couple of weeks.)

Not sure what i was thinking but I hit the aftermarket remote start and tried to start the car. As i suspected, the car failed to start but it was clicking like a dead battery would. The odd thing was the remote start kept trying to start the car over and over. So i hopped in and put the key in the ignition and turned it on. That didn't work and it kep going. So, to not damage any components i disconnected the battery.

Now i was a bit confused about the remote start. I have been around a good number of them and i thought they had a failsafe and stopped after 3-5 trys. This one kept on going. So i reconnected the battery and tried to start it with the key. Same issue, no start just the starter clicking. I then jumped the car with my jeep. The car now has full power, but when i go to start it up i hear nothing at all. Not even the starter clicking.

Confused as to what was going on i thought the starter had gone bad. When i removed it and did a bench test, it was in good working order. So i reinstalled it. After all this i tried to restart the car with the remote start again thinking there was a security feature with the remote start. No luck. So i located the remote start and disconnecteed the entire control module from the car.

Here is where I'm at now. With the remote start control module disconnected, and with the original battery in, When i start the car, the starter clicks like there is a dead battery(makes sense). BUT when i jump the car with my Jeep and now have full power to the subaru I get nothing. Not even the starter is clicking. Although i do hear clicking coming from the left of the car and the right.

At this point I'm at a loss. I am picking up a new battery today for it, but i still don't understand why it won't start, or even engage with full power, but it will with half a dead battery. Please help!
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Just to clarify, the clicking I am hearing is the starter relay, I believe the electronic throttle, and another solenoid on the right side of the car behind the glove box(body control module relay/security relay???)
Okay, so it's not the starter solenoid ("magnetic switch") that's clicking.

At the back of the starter solenoid there's three connections. Two are heavy bolted connectors. One of these has the cable coming from the battery; the other has a wire going down into the starter motor itself.

The third is a small, single wire with a spade-type push-on connector. This is the one that provides power to the solenoid when the key is at the Start position. If this hasn't been done, I suggest measuring the voltage at that connection; when the key is turned to Start there should be approx 12 V.

If there's approx 12 V there, then the starter solenoid is bad. (It isn't activating to connect the heavy battery cable through its internal contacts to the starter motor winding.)

If there isn't approx 12 V, then there's a problem in the starter system. The inhibitor switch and the starter relay are involved, but also the security system through the body integrated unit and security relay. I've attached a wiring diagram which I believe applies to your car.

The aftermarket remote start system could be a factor as well. I have no experience with these, but from what I've read here, they aren't just "plug and play"; installation involves some wiring changes. If this is the case, then they can't just be disconnected to take them out of the system. Rather, once they're disconnected, the wiring of the car has to be returned to the original state. If that's the case (and I recognize I might be wrong), then troubleshooting might require more than just disconnecting the remote start module.


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Now I only took the voltage(no test light) at pin 16 while trying to start it, It didn't start BUT was giving me 12 volts??
Quite normal.

With the key at Start, the 12 V from pin 15 of the starter relay will go through the starter relay energizing coil wire and appear at pin 16 as long as pin 16 isn't grounded. This is a Voltage measurement, and applies when no appreciable current is flowing.

The relay coil typically requires only about 100 milli-Amps to work. Most test lights will pass far more than that current, so when you connected the test light between pin 16 and ground, you provided a path for current to flow through the starter relay coil. This activated the relay, closing the connection between pins 13 and 14, which in turn energized the starter solenoid. But when you connected the Voltmeter to pin 16, the relay couldn't activate because the Voltmeter doesn't pass very much current, and so the car would not start.

Clearly what is happening is that the Security relay is not closing, thereby preventing the current from flowing through the starter relay coil, and preventing the starter relay from closing. I doubt the security relay is bad; instead, I suspect the Body Integrated Unit isn't activating the Security relay as it should. And, interestingly, it all started when the battery was run down.

There was another thread with a very similar situation with a 2005. It's a long thread, but probably worth looking through. There were a lot of tests done (and searching for various relays etc), and the outcome was a bit of a surprise. See:
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I think i found the BIU but like i said before it doesn't seem to match the wiring diagram plainOM attached.
It's possible that the wiring colors have changed; as cardoc noted, that's been seen before. However, the connector at the BIU (B280) has 30 pins, so finding the right one (pin B10) can sometimes be challenging.

The connectors that are shown at the bottom of the attached wiring diagram show the numbered positions of the pins on the harness connector when looking at it face on. When looking at the connector from the back, as when it's still connected to the BIU, everything is reversed. This has also led to confusion in the past.

Also should have noted that the BIU has three large connectors, designation A, B, and C. The connector that has the wire going to the Security Relay is B ("B280"), which I presume is probably the middle one. I've attached a diagram showing the location of the BIU, it's connectors, and what some of the connections are, from the 2005 manual.

In order for the car to start, it appears pin 1 of the security relay has to be high (see this post) and pin 2 of the Security Relay has to be "low". Presumably pin 1 will he high if the security system, which is incorporated in the BIU, has been dis-armed. Pin 2 will go low when the ECM detects that the inhibitor switch is in P or N. So there's two possibilities that can be checked and might help narrow down the cause. (These were observations in the linked thread; useful but not suggesting the Tribeca route!)


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. . . The one thing I noticed last night was the car starts in any gear, not only in park or nuetral. I noticed it when i was putting the interior back together to make it drivable and testing out everything. Could this be because i made a jumper for the relay and it is no longer connected to the security relay/BIU or have I just found the root cause?
If your jumper is from terminal 16 of the starter relay to ground, which I believe is where you put the test light, then the relay will be energized whenever the ignition key is turned to Start and there's 12 V at terminal 15. You are indeed bypassing not only the security relay function, but also the interlock function of the inhibitor switch and the ECM (Park or Neutral start only).
Has the neutral switch been checked?
Not that I can recall being reported here.

The AT, of course, has the inhibitor switch, rather than the neutral position (safety) switch, and the P contacts relating to the starter system interlock could be open. This might be quickly verified by setting the key to ON, moving the gear to N and then see if it will start. (With the jumper removed!) It's not likely that both the P and N contacts would be bad while the car can be driven normally once the engine is started. But the question is quite relevant.
B10 (B280 Connector) - 0V on, 5.69V Cranking.

Now before that, I was testing the same connector and I got 12.18v on and 12.14v cranking, although i might have had a different wire being probed by accident.

I thought there would've been 12v going to the BIU not the 5.69 i recieved? I also jumped B10 to ground to see if it would start(effectively eliminating the BIU from the root cause?) and it didn't start.
I'm not sure this is all that unusual presuming that you're at the right terminals. First, let's set aside the previous readings because we're not sure they were at the right terminal. (Might have been, but at this point only adds uncertainty.)

The 0V on, and 5.7 V cranking seems to make sense, as does the next test where B10 was grounded and still no start. In this regard, in post #76 in the linked thread, and as I noted earlier, it appears that the security relay is "normally closed"; that is, there's a connection between terminals 2 and 5 when terminal 1 is "high". That's a condition that needed for the starter relay to close. But if, during cranking, there's 12 V at security relay terminal 3, and 5.7 V at terminal 1 (B10), then there's current flow through the energizing coil, and the connection between terminals 2 and 5 is probably switched open. (See the diagnostic section diagram attached in post #76)

In the linked thread, in post #77, we're told that the mechanic cut the wire to terminal B10 of the BIU and the car started. In other words, terminal 1 was forced "high". I wonder if if you were to do the same thing, the car would start fine. If so, then we would know it's the BIU that's preventing the start-up, perhaps because of some security system glitch.

I think you're on the right track, and getting close, but would suggest the same B10 "high" test before turning to the ECM because your symptoms and those in the linked thread are all too similar.
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It does seem as if the BIU is inhibiting the start. I tend to doubt it's a fault with the BIU itself; more likely something akin to the linked thread where an external issue was triggering the BIU security system to prevent starting.

In the linked thread, the "key" seems to have been the technician "forcing" the car into a diagnostic mode. In this regard, the Subaru Select Monitor III can be used to look at all the control modules to see if there's anything amiss, and it can also check various functions, such as door lock actuators, to see if anything is not working properly. (All of these are controlled by, or data is processed by, the BIU, which is not only a controller but a "central station"/router for data transmission.) Unfortunately, this requires a visit to a dealer.

I wonder if a similar problem has been discussed in other venues, such as, or one of the several Legacy forums.

Incidentally, when the car is started and running, does the trip meter read correctly?
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