06 Tribeca/EZ30R Charging System Issue

[06b9beca]

I couldn't post this in the electrical forum, so I am posting here.

 

Since getting my EZ30R equipped Tribeca back from the JDM shop I have not been able to resolve the following issue:

I am experiencing a poorly charging electrical system with all accessories running at idle. The vehicle starts off charging at about 14.4 VDC, but after about 2 minutes of running voltage dips down to about 12.2 VDC and continues to fall.

Idle is about 750 rpm. Current Draw is about 78 Amps with all accessories running as checked with my DC clamp meter.

The low voltage appears at the alternator terminal, not just the battery terminal.

I tried grounding different parts of the engine block to the battery negative terminal to no avail.

The vehicle has a brand new Advanced Auto Autocraft Gold battery and I have tried alternators from both engines to no avail.

If I rev the engine up a few hundred RPM(s), the alternator is able to reach 13.8 VDC.

HISTORY:

I recently had a JDM engine put in by a JDM engine shop due to a head gasket issue on my EZ30R Tribeca.

Since I got the vehicle back, it has naturally had a few issues. First the power steering pump whined away and was dumping fluid onto the top of the motor. I asked for my old pump back and that worked with the exception of a small unknown leak at the pump. Unfortunately my old pump was missing the sensor with the wire at the back of the pump. It seems like the shop broke that off and put the JDM pump on instead.

I only mention this just in case that disconnected wire might be the cause of my issue. I doubt it because I connected the JDM pump wire to that wire after installing the original pump and grounded it. I ran the engine and the voltage still continued to drop so that wire likely has nothing to do with it.

The JDM shop is pretty far away so it's a MAJOR hassle to get it back over there.

SIDE NOTE:

I had the EXACT same thing happen to my Dodge Caravan and no one could ever answer.

In that enthusiast forum, the first week or so were arguments back and forth about whether or not the alternator could actually maintain voltage with all accessories running at idle. Come on now, these are family vehicles and the Tribeca is a luxury vehicle! I'll NEVER believe that voltage is supposed to go so low that your rear blower motor fan shuts off! I could be stranded with my family if I get stuck in the every day 50 mile bumper to bumper traffic encountered in the DC area!

The second week or so I was able to convince someone to check their voltages with all accessories running and they confirmed voltage well above 12.5 VDC.

The third week or so I purchased a clamp meter where a few folks mentioned that the current draw at idle was a bit too high, but could offer no solutions as to why.

The 4th week or so I ended up giving up and getting a heavy duty alternator which burnt up in no time.

As a result, for the last 4 years I have run a smaller alternator pulley on that Caravan which allowed me to get more alternator juice at idle. Unfortunately, I have to replace the alternator every 8 months and hope that it didn't burn up in the middle of a long trip with family and pets aboard.

In that case, I re-grounded everything with thick gauge wires and ring terminals to no avail and the grounds on this Tribeca are pretty doggone hard to reach.

I feel like I am headed for a repeat with this Tribeca and I'd rather sell it as is than drive myself insane or delegate it to "junk pickup" duty like I did with my Caravan.

I think that is just going to be an unsolvable issue!

Can anyone help?

Thanks!

[Gloyale]

So.....you might have an issue.

 

But I would submit that what you are seeing is the initial "recovery" charging of the battery after it discharges hundreds of amps to start car.  Alt pushes maximum output about 14.4 volts.....As battery recovers, and fewer amps are needed the amount of charge drops, and the VR levels out the voltage accordingly.

 

Subaru systems don't run at 14+ volts all the time.  Closer to 12.5, which is close to what you are reading.  And load testing it with 78 amps of draw is pretty close to the max output of 110 which happens at higher RPMs.....the alt cannot produce 75% of max amps at idle.  I don't think the engineers designed it to idle long time with ALL items on.  They figure your gonna drive, not idle with the lights and blowers and wipers all at max.  Running up the RPS a few hundred brought it to 13.8?  sounds like it's working to me.

 

If the voltage tries to drop below 11.x then there is an issue.

Edited October 21, 2017 by Gloyale

[06b9beca]

So.....you might have an issue.

 

But I would submit that what you are seeing is the initial "recovery" charging of the battery after it discharges hundreds of amps to start car.  Alt pushes maximum output about 14.4 volts.....As battery recovers, and fewer amps are needed the amount of charge drops, and the VR levels out the voltage accordingly.

 

Subaru systems don't run at 14+ volts all the time.  Closer to 12.5, which is close to what you are reading.  And load testing it with 78 amps of draw is pretty close to the max output, which happens at higher RPMs.....the alt cannot produce max amps at idle.  I don't think the engineers designed it to idle long time with ALL items on.  They figure your gonna drive, not idle with the lights and blowers and wipers all at max.

 

If the voltage tries to drop below 11.x then there is an issue.

 

Thank you very much. If left alone it drops down to the 12.2 range and continues to decline. I am going to let it run and report back. So apparently this model has an external regulator which is regulated from the ECU. My 04 Forester XT doesn't act like this. I can idle it all day and get it to stay in the 13.x range with no problems. 

 

Next time around the draw was only 68.x amps at idle. (After I recharged the battery, but the 12.2x situation exists) It still takes longer.

[1 Lucky Texan]

if there's really a problem, any chance a rebuilt alternator was installed? parts stores often supply the 2.5l version, or just a bad alternator.

[06b9beca]

if there's really a problem, any chance a rebuilt alternator was installed? parts stores often supply the 2.5l version, or just a bad alternator.

 

This has the same part number as the other EZ30R alternator though. I see what you are saying. This looks like it came off a JDM engine...came right from the JDM shop. Of course, looks mean nothing, but the likelihood is much higher that it was just an accessory from Japan.

 

I am going to rescind upon my Forester's activity statement.

 

I turned on everything including the heated seats and it also dropped down tot he 12.xx range at idle at around 58 Amps and I have never ever feared being stuck in that vehicle especially when it came to the electrical system.

 

I wonder if this was some EPA thing that got implemented at some point that I hadn't noticed. My Van's issue might be different.

 

HMMMMM

Edited October 21, 2017 by 06b9beca

[06b9beca]

I turned on the front and rear dewipers and it dropped down to 11.8x VDC. I mean, I'd guess that no human does all of this for long at idle but this is rather low no?

[golucky66]

While i do believe there might be an issue with a failing or weak alternator. But i literally just installed an alternator on a 2006 Acura 6 cyl. (i know not the same brand) but max output of the NEW alternator was 75 amps at idle.

That's actually a heck of a lot of amp for idle (~750 rpms)

 

Vehicle truly aren't designed to have every accessory running for a long period of time at idle. They'd have to put 200 amp alternators on 4 cylinder engines just for it to output 100-125 amps at idle. And that's a HUGE load on the engine.

[06b9beca]

While i do believe there might be an issue with a failing or weak alternator. But i literally just installed an alternator on a 2006 Acura 6 cyl. (i know not the same brand) but max output of the NEW alternator was 75 amps at idle.

That's actually a heck of a lot of amp for idle (~750 rpms)

 

Vehicle truly aren't designed to have every accessory running for a long period of time at idle. They'd have to put 200 amp alternators on 4 cylinder engines just for it to output 100-125 amps at idle. And that's a HUGE load on the engine.

What do you think is a normal load at idle? 

[golucky66]

Normal depends in environment. If it's winter time where you live. It's normal to have blower maxed, wipers on (maybe) heated seats, mirrors, wipers, rear defrost, radio. All drawing 75+ amps.

Which is completely fine. Because the systems designed to handle that load. Just not for extended periods of time at idle.

They expect that load to be that high for maybe 10 minutes. All of which typically yous be driving the car. Not idling it.

 

If you test your alternator at idle and can get ~75 amps out of it. Honestly,it's probably working fine.

 

And just to be sure have someone load hold the rpm up, and see if you can get it to go higher.

(in a shop environment, we can artificially add a load to the system and see what the alternator an peak at) subarus i believe have a 110 amp alternator. H6's might have slightly higher but still.

[06b9beca]

Normal depends in environment. If it's winter time where you live. It's normal to have blower maxed, wipers on (maybe) heated seats, mirrors, wipers, rear defrost, radio. All drawing 75+ amps.

Which is completely fine. Because the systems designed to handle that load. Just not for extended periods of time at idle.

They expect that load to be that high for maybe 10 minutes. All of which typically yous be driving the car. Not idling it.

 

If you test your alternator at idle and can get ~75 amps out of it. Honestly,it's probably working fine.

 

And just to be sure have someone load hold the rpm up, and see if you can get it to go higher.

(in a shop environment, we can artificially add a load to the system and see what the alternator an peak at) subarus i believe have a 110 amp alternator. H6's might have slightly higher but still.

 

Yep, I can get the voltage to stop dropping if I rev it to about 1000 RPM.

 

With 2 alternators doing the same thing, and the reputation of these Mitsubishi Alternators, I'd doubt this is an alternator problem. Top it off with my Forester XT acting the same way I seriously doubt it's an issue.

 

You have some good points.

 

What do you figure current draw might be with everything turned off? I have an accessory in there that I tend to forget about. Aftermarket GPS and radar detector. Also, the DRL's will be on and they are Osram Rallye bulbs 65 Watts when running as low beams.

 

Would be nice to have a baseline. Very few Tribecas around though.

 

Thanks.

Edited October 22, 2017 by 06b9beca

[golucky66]

Typically on most cars, with a good battery, and the system functioning properly. Without headlights (or drls) or any accessories, after about 3-5 minutes,the alternators output shouldn't be much more then 5 amps or so if i remember correctly.

 

There's really no electrical load to keep the engine going. Power up modules, fire injectors and spark plugs, fuel pump at 33% or less duty cycle.

[golucky66]

With drls and your radar detectors and gps, 10ish amps is probably normally. Maybe up to 15.

[06b9beca]

Thanks for the data. Going to check against my Tribeca and FXT. If they both act the same then I think we have concluded.

 

I do think that the Tribeca is drawing about 40 amps with the Radar Detector/GPS running and the DRL at idle though.

 

Then again, I have a cheapo clamp meter....gotta wonder if it's accurate. It's usually not like the old days though where you had to spend big bucks for accuracy.

 

Will check into this.

[golucky66]

40 amps at idle sounds really high. That would be with like headlights on (full) and other accessories like blower medium to high, radio etc... 

 

I could be wrong, I don't really ever have to deal with "normal" idle ampere draw. Just trying to remember from some odd ball training classes i've gone to and some cars I've experimented on. 

[06b9beca]

40 amps at idle sounds really high. That would be with like headlights on (full) and other accessories like blower medium to high, radio etc... 

 

I could be wrong, I don't really ever have to deal with "normal" idle ampere draw. Just trying to remember from some odd ball training classes i've gone to and some cars I've experimented on. 

 

Does it matter which side I check? Negative or positive terminal? Do I check all wires going to that terminal and add the total amperage together?

 

Thanks.

[Gloyale]

Does it matter which side I check? Negative or positive terminal? Do I check all wires going to that terminal and add the total amperage together?

 

Thanks.

 

just test the Alt output wire.

 

unless you want to know what each device uses specifically.

[06b9beca]

just test the Alt output wire.

 

unless you want to know what each device uses specifically.

 

I was afraid you'd say that. I don't even want to talk about the draw on the Alt output wire without accessories. 

 

I think that I'd do best to make sure that the battery is charged next time I measure, but IIRC the draw on that wire is like 30A with no accessories. 

 

The FXT is not far behind though at 15-20A with no accessories.

 

I cannot get any real readings on the negative battery terminal which I find strange. Something like 2.5A. The FXT is similar though.

 

Also, the 30A drops to like 22A as I go down the wire. Wondering if it's the cheap meter that I am using. I'd still doubt it. Come to think of it, it is probably interference from the Alternator's spinning so I'll measure further downstream.

 

Has had good reviews historically:

 

 

One thing that comes to mind is that I am getting the red ring around the ignition indicating Factory Mode as opposed to Market Mode. Doubt that is the issue, but I recall something about that drawing more current. Too cheap to have it reset...especially by my local two star/two bit local dealership.

 

Thanks for your help so far!

Edited October 22, 2017 by 06b9beca

[06b9beca]

So here are the final results.

 

FXT - Warmed up with charged battery....lowest current draw on cable at idle 9A-12A.

Tribeca - Warmed up with charged battery....lowest current draw on cable at idle 19A-20A 

Tribeca - Warmed up with charged battery....lowest current draw on cable with Headlight fuses removed to stop DRL 12A-14A.

 

I suspect that this is all normal especially with the voltage drop on the FXT doing pretty much the same thing under load.

 

The Tribeca has a few things that can't be shut off that the FXT doesn't (as far as I know anyways). Central Trip console which displays a laundry list of parameters. Numerous lit interior buttons like door switches, etc. 

 

I also have an overhead DVD player in the Tribeca which was shut off but will still draw minimal current.

 

There is only a 2-3 amp draw difference between the 2 if the DRL's are discounted.

Edited October 22, 2017 by 06b9beca

[golucky66]

Personally I'd say your results are normal. The Tribeca has more modules then any other Subaru of the same MY. And more things to power up because it's the "premium" car.

[06b9beca]

Personally I'd say your results are normal. The Tribeca has more modules then any other Subaru of the same MY. And more things to power up because it's the "premium" car.

 

Yeah, I am hoping so. Thanks for your time. Going down the road with no accessories today, I saw a couple of spots using Torque Lite where it seems the ECU was shutting down the alternator completely...so I was at battery voltage for about 20 seconds and then back to normal and then back down to battery voltage.

 

Looks like the ECU can control this in favor of fuel economy.

 

Check out the "cross-thread" on the outback forums:

 

http://www.subaruoutback.org/forums/80-electrical-electronics/451329-06-tribeca-ez30r-charging-system-issue.html

Edited October 22, 2017 by 06b9beca

[06b9beca]

Found this!

 

http://strongforsubaru.com/subaru-alternator-fault-fix/