Subaru Outback Forums banner
  • Hey everyone! Enter your ride HERE to be a part of December's Outback of the Month Challenge!
1 - 8 of 8 Posts

·
Registered
Joined
·
11 Posts
Discussion Starter · #1 ·
Hi all,

Today I was driving our 2009 Subaru Outback when suddenly I noticed the odometer display showed an Er IU above the total mileage on the car. Additionally, the ABS, Traction control, and brake lights were all flashing intermittently. I also noticed that the car seemed to be acting like the battery was dead or dieing. The signs of this were higher electrical performance when accelerating (IE blower motor on the fan motor for the AC increased).

I took it to the auto store and had them test the battery. They couldn't find anything wrong with it and said it was outputting pretty much the expected values on the label. I then let the car sit with the battery out for about 10 minutes to give the ECU a chance to reset. Upon reconnecting and turning the car on, I'm still seeing the Er IU message along with an Er 55 intermittently above the odometer mileage. The headlights aren't working, but turn signals work, brake lights work, and hazards all appear to work. Interior lights (with the door ajar) don't work now unless the car is off.

I went through the interior fuse box (drivers side) and tested all the fuses for voltage and I had success with my electrical light probe. I also tested all of the fuses in the fuse box in the engine bay with the same results.

I'm planning to take the car to a local mechanic tomorrow given I don't think I will be able to do much with this if it's an ECU issue. Any recommendations on what I can additionally check/try?

I took some videos in-case this might be of assistance (IE the interval between light flashes).


Thanks in advance and let me know if I can provide any further details!
 

·
Super Moderator
Outback 2011 3.6R Premium
Joined
·
2,959 Posts
It will not be an ECU issue. Subaru ECU’s rarely if ever fail.

The ER IU error relates to a Body “Integrated Unit” fault.

The ER 55 error relates to an ABS fault.

You will need to attach a code reader to the OBD2 port and scan the ABS and BIU modules to obtain the actual error codes that have been set.

Are your battery cables tight and free of corrosion?

How old is your battery, a failing battery may be the cause of these errors?

Just because a battery passed a voltage test does not mean it is good. A CCA (Cold Cranking Amps) test needs to be done to compare the batteries rated capacity to its actual capacity.

Hope this helps.

Seagrass
 
  • Like
Reactions: cardoc

·
Premium Member
01 VDC, 05 R Sedan, 06 BAJA EJ257
Joined
·
16,482 Posts
Bad grounds.

You could also have a couple different issues happening at the same time. The ER 55 is actually an error with any of the 4 speed sensors on the car with the 55 = SS for speed sensor. It's either related to bad grounding or you have a speed sensor issue. A speed sensor issue could be a broken or chaffed wire on the sensor harness, or it's a failing/failed wheel bearing.
 

·
Registered
Joined
·
19,515 Posts
In the second video, the engine is running but both the Battery and Brake warning lights are on at the same time.

I don't see the same in the first video.

Was the parking brake applied during the second video, but not in the first?

When both the Battery and Brake warning lights are on at the same time, that's usually an indicator that the alternator is not working. When the alternator is not supplying the system, the battery voltage drops. The ABS/VDC control module is sensitive to the supply voltage, and when the latter is low, the ABS and other related warning lights often appear.

This doesn't directly address the ER indications, but if the alternator is failing, it could also affect the CAN communications system.

As others have noted, charging circuit wiring, including grounds, could be involved in the alternator not operating properly.
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #5 ·
It will not be an ECU issue. Subaru ECU’s rarely if ever fail.

The ER IU error relates to a Body “Integrated Unit” fault.

The ER 55 error relates to an ABS fault.

You will need to attach a code reader to the OBD2 port and scan the ABS and BIU modules to obtain the actual error codes that have been set.

Are your battery cables tight and free of corrosion?

How old is your battery, a failing battery may be the cause of these errors?

Just because a battery passed a voltage test does not mean it is good. A CCA (Cold Cranking Amps) test needs to be done to compare the batteries rated capacity to its actual capacity.

Hope this helps.

Seagrass
Thanks, to clarify the battery test I had performed was a CCA test and that's what I meant by it matching the label (IE the expected CCA output). The battery I believe is from August of 2018 IIRC from the side of the battery. Battery cables are tight and free of corrosion from what I can tell.

This morning, things got even weirder though. I went down to the car and it was totally dead. I was able to jump it with my battery jumpstart. After I got it going though, all the error codes on the odometer are gone. I went to another auto parts store and had them run a battery test. They said the battery was fine, just needed a charge. They were unable to do an alternator test given how low the battery's charge was.

One more point to point out is I actually took an OBD2 scanner down this AM and checked for confirmed faults, pending faults, and historical and I was unable to pull any, so I think they're long gone with the battery being going dead overnight.

Bad grounds.

You could also have a couple different issues happening at the same time. The ER 55 is actually an error with any of the 4 speed sensors on the car with the 55 = SS for speed sensor. It's either related to bad grounding or you have a speed sensor issue. A speed sensor issue could be a broken or chaffed wire on the sensor harness, or it's a failing/failed wheel bearing.
This seems plausible, but the timing of it and the behavior of other features in the car make me think this is an erroneous code and caused from something else. Specifically, the lack of headlights when I turn them on for example makes me think something else is going on.

In the second video, the engine is running but both the Battery and Brake warning lights are on at the same time.

I don't see the same in the first video.

Was the parking brake applied during the second video, but not in the first?

When both the Battery and Brake warning lights are on at the same time, that's usually an indicator that the alternator is not working. When the alternator is not supplying the system, the battery voltage drops. The ABS/VDC control module is sensitive to the supply voltage, and when the latter is low, the ABS and other related warning lights often appear.

This doesn't directly address the ER indications, but if the alternator is failing, it could also affect the CAN communications system.

As others have noted, charging circuit wiring, including grounds, could be involved in the alternator not operating properly.
Good clarifying point, in both videos I didn't actually engage the parking brake or e-brake. As I mentioned in the reply to the quote above, I'm leaning towards the Er 55 being an erroneous code honestly.

I'm also beginning to lean towards this being a faulty alternator actually given some of the behavior. Would this cause some weird things like being unable to take the car out of Park and Into reverse or the headlights not working when I flip them on?

I did drop the car off this morning with the mechanic given all of the Er codes are gone and the headlights still don't work since all this started. Overall this behavior is really bizarre and doesn't exactly align with what I'd expect a car to do when there is an issue with generate amperage, etc.

Thanks again!
 

·
Premium Member
01 VDC, 05 R Sedan, 06 BAJA EJ257
Joined
·
16,482 Posts
Ampere flow through the engine block/trans and the body is the most important item and when it's low all kinds of things pop up, don't work, act stupid, because there's not enough electricity to go around. The alternator is affected by the grounding and needs a good ground system to operate. A conductance test between the battery positive cable and the alternator case will tell. If the ampere drop is more than 75A, the grounding is bad.

The headlights though, that's a weird one. Do the DRLs work? This may be a fault in the combination switch, or anywhere between it and the lights. It could be related to the power issue, but generally they will come on, just really dim.

In checking the alternator output, a weak battery can still allow for the alternator to be tested under load. With the car idling, you monitor voltage output while you turn things on in series. Headlights on, AC on full, brake pedal depressed, radio on, put the car in Reverse, to turn on the reverse lights. This puts an electrical load on the system, especially the AC compressor, and if the voltage drops at idle, speed the car up to above 1200 rpm and see if the voltage comes up. If it does, it's a grounding issue. If it doesn't, it's the alternator.

Here's an example on an LL Bean with a 3.0L (EZ30D).
 

·
Registered
Joined
·
19,515 Posts
Would this cause some weird things like being unable to take the car out of Park and Into reverse or the headlights not working when I flip them on?
Those symptoms are often due to blown fuses, in some cases caused by shorts in the wiring to the rear gate.

Do the backup (reverse) lights work? The backup lights are powered by fuse #18 in the cabin fuse box. It also powers the DRL control module. The Module controls the headlights and the fog lights. So when the backup light fuse is blown the headlights don't work.

Do the brake lights work? Does the cargo area light work, and do the the front door step lights work when the door is opened? These are powered from fuse #8 in the cabin fuse box. Fuse #8 also powers the shift lock solenoid control circuit. If the fuse is blown, not only do the stop lights and interior lights not work, but the shift lock control won't release the gear selector so that it can be moved into or out of Park while the brake pedal is being pressed.

All of the symptoms have been seen many times in relation to the broken wires. More details can be found in this thread and in the threads for which links are provided therein: Replace '05 Outback hatch wiring harness?

Also, the second video begins with the Battery and Brake warning lights on, the trip meter indicating mileage and the ABS and VDC warning light turning on and off. When the engine rpm increases, the trip meter had changed to "ER SS" and the ABS and VDC warning lights appear to be on solid.

The alternator should be tested for operation, including the appearance of AC ripple in the output that could indicate a shorted diode inside. Excess ripple would reduce the ability of the alternator to charge the battery, and can affect the operation of the electronics of the ABS/VDC and the BIU.
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #8 ·
It was the alternator! The positive terminal/bolt area was melted on the alternator. They think there was a short. Regarding the headlights, apparently both bulbs were blown. Apparently no fuse blew for that. The shifter being unable to go from park to reverse only happened once yesterday for what it's worth and then after I restarted the car it was fine.

Also had them swap the battery as it's over 3 years old now and I'm not trying to deal with a dead battery this winter.

Thanks for all the help and glad to have it all sorted now!
 
1 - 8 of 8 Posts
Top