Subaru Outback Forums banner

1 - 20 of 25 Posts

·
Registered
Joined
·
23 Posts
Discussion Starter #1
i was swaping out a POS reman alternator for a salvage oem alternator today and the green pigtail crumbled to pieces in my finger tips. anyone know what the part number to this wire assembly is? runs from the fuse box to the alternator and plugs in with the green pigtail ontop of the alt.
 

·
Registered
06 OBW 2.5, 05 Forester, had 03 H6 OBW
Joined
·
5,936 Posts
Ohhh, was it a reman of a genuine subaru?
Aftermarket alts do not fare well in the H6's.

best bet may be a junk yard for that piece, and it is H6 specific.
 

·
Registered
2003 Outback H6
Joined
·
134 Posts
I think thats what he said he did, removed junk reman, put in salvaged OEM.

As far as the plug goes, will probably have a hard time finding just that plug as part of a harness. Might have to just find a pigtail and splice it in. Honestly don't know what it looks like as I haven't gotten that far into the engine yet, but quick search on ebay popped this up, its green so might be it. Although this one looks like a little more work, would actually have to snip wires off right at plug, and use the terminals crimped around wire, and then slide and lock into plug.

Subaru Alternator Wire Harness Plug Kit Oval Green WRX Impreza Legacy STI 2 5i | eBay
 

·
Registered
Joined
·
23 Posts
Discussion Starter #4
Thanks for the replys. I went back to the salvage yard I pulled the oem alt from and purchased the green pigtail for 5 bucks. I spliced into place, soldered it for good measure and used shrink tubing over each of the 3 wires I spliced. Car runs smoother than ever. My battery light is on but it's for my battery. Alternator is reading 14.6-15 volts in freessm. Car cranks over no problem even though battery light is on. Battery sat for a year unused.
 

·
Registered
Joined
·
18,285 Posts
Better make some measurements. If the alternator is putting out 14.6-15 V according to FreeSSM (which is the voltage measured by the ECU at the ECU (under the front passenger foot well carpet), and the battery warning light is still on, something doesn't seem right.
What's the voltage at the battery terminals?

(The battery warning light is connected, in effect, between the battery positive terminal and a separate set of diodes ["diode trio"] in the alternator that provide output for the field coil and warning light when the alternator is working. If the light remains on after the engine is started, then either the battery voltage that's on one side of the bulb is significantly higher, or lower, than the output from the alternator diode trio, which is not correct. It could indicate a badly discharged battery, a problem in the alternator, or in this case, a mis-connection.)
 

·
Registered
Joined
·
23 Posts
Discussion Starter #6
my battery was an ever start maxx 35n from Walmart. they replaced it free under warranty because it was less than 3 years old and wasn't holding a charge. I took the reman alt to pepboys where I had originally bought it and it tested defective. it has a lifetime warranty so I was given a new reman alt from them. Im going to replace the oem salvage alt with the warranty replaced reman alt because the battery/alt light is still on with the new battery. its snowing outside and dark right now. it will have to wait until the morning. ill report back. thanks for the help.
 

·
On the Super Mod Squad
2002 3.0 VDC Wag + 2018 2.5 Leg Ltd
Joined
·
26,307 Posts
I wonder if you got bad battery wires. (have to slice open the sheath to look, and quality retape it or reshrink it if you got some that big)

. the H6 OEM alternator runs with the ECU. but whatever Pepboys sells you will not work with this car. (and will only leave you p;ssed off in the snow,...possibly alongside the road waiting for a flat bed).

maybe you got a dud from the parts yard. so that leaves you with a GOOD Used one from a parts yard, subaru dealer OEM reman

, plenty of threads here on the subject of the H6 alternators for Gen2 and you can thank pep boys and the guarantee/ warranty fairy. (a few I post the following on).

 

·
Registered
Joined
·
23 Posts
Discussion Starter #8
Bat/alt light is still on. with the car off the new battery reads 12.6. with the car on and warm after a 30 min drive the new reman alt reads 15.3 at the battery posts and at the positive terminal on top the alternator. sound like a bad voltage regulator? what should the alt read when the car is at operating temperature? 14.2-14.8?
 

·
Registered
Joined
·
18,285 Posts
15.3 at the battery posts is too high.

After warming up, and replenishing the battery, I would think it should be closer to 14 V. But the H6 alternator, which is partially-controlled through a connection to the ECM, will often be lower; the ECM lowers the charge rate to reduce the load on the engine.

Is the battery warning light lit up as bright when driving as when the key is turned to ON but the engine not yet started? With the engine running, does the brightness of the bulb vary with the engine speed? Is it brighter at higher rpm, or less bright?

Are you sure that the spliced-in connector was wired exactly as it was before? The three wires are important for proper operation of the alternator, including regulation. The fact that the battery warning light is on could mean that something wasn't put back the way it should be.

Was the alternator from the salvage yard, that is in the car now, from an H6?
 

·
Registered
Joined
·
23 Posts
Discussion Starter #10 (Edited)
wires are spliced correctly. im not color blinded, I mean that with no attitude. I appreciate your input and know youre helping me rule things out. the battery light is as bright at idle as it is when accelerating and maintain speed. nothing in the car dims with change in rpm or load. the salvage alternator reads 13.2-13.3 volts at the post and is no good. the warranty replaced alt is reading 15.25-15.35 at the posts. the alternator before the warranty replacement lasted for 3 1/2 years until it was only at 13.5 volts and determined to be defective. im really kinda stumped about this. 15+ volts I too much I feel. im gonna pull it out after work tomorrow and see if it meets the stores standard for voltage regulation. I am considering getting new battery cables. does part 5 look to be correct for a 2003 h6? FYI I returned the salvage alternator and it was from an H6 ll bean.


 

·
Registered
Joined
·
23 Posts
Discussion Starter #11
I also agree whole heartedly about the warranty alternator. seeing your chris farely is exactly what I thought of when I was in line to get it replaced and its how ill feel when I go back tomorrow. unfortunately its what I've got until I can find a functional OEM salvage alternator with good voltage and no unbearable whine.
 

·
On the Super Mod Squad
2002 3.0 VDC Wag + 2018 2.5 Leg Ltd
Joined
·
26,307 Posts
I also agree whole heartedly about the warranty alternator. seeing your chris farely is exactly what I thought of when I was in line to get it replaced and its how ill feel when I go back tomorrow. unfortunately its what I've got until I can find a functional OEM salvage alternator with good voltage and no unbearable whine.
does that one from the salvage yard say Hitachi or Mitsubishi on it?

I think those are the only 2 companies that made H6 EZ30D alternators.

unfortunately the parts stores, want to sell you things that fit many cars, and this particular part is unique to the EZ30D cars,...although they will say "yep it fits, our computer don't lie":toothless

look at it this way,...in 10 years when you are looking for parts for your LFA you will also have to avoid Pep Boys for its alternator.

 

·
Registered
Joined
·
23 Posts
Discussion Starter #14
plain oem I just realized I miss read ur question about the bat/alt warning light. with the car off and the key in the ON position the warning light is bright. when I start the car the light stays on and is a little brighter than with the car off, key at ON. with the car on at idle, with the left or right turn signal on, the bat/alt light dims in conjunction with the turn signals but not a significant dim. can only tell when I am concentrating on it. the salvage alternator voltage was at 14.3 with the old battery. with the new battery it was 14.0. went to bed and the next morning it was in the 13's and not charging the battery so that is why I have the warranty reman back in h6. salvage alternator also made a loud whine that would quiet after warm but still made the car sound like a clunker.
 

·
Registered
Joined
·
18,285 Posts
Actually, the salvage alternator voltage, "in the 13's", sounds better than in the "15s"!

I'd make a number of measurements to try to isolate the issue.

First, don't assume that the voltage measured between the battery positive and negative posts is the same as the voltage output of the alternator when the engine is running. It normally should be close, and that is what should be looked for, but wiring problems could cause it to be different.

With the engine OFF, the battery voltage (i.e., at the battery posts) should be around 12.7 V. Also, the voltage measured between the large output connector on the alternator and the alternator case should be the same.

With the engine running, the voltage at the battery posts, and the voltage between the large alternator connector and the alternator case both should be around 14 V. (Granted it could be lower, or higher, but there's a reasonable range -- probably between 13 and 14.8 or so -- beyond which it should be checked, or compared to another H6 Subaru.)

With headlights, interior lights and heater fan turned on (in other words to put additional load on the system), and the engine running at around 1000 rpm, measure the voltage between:

1) battery negative post and the alternator case.

2) battery negative post and a good ground on the car body.

3) large alternator output connector and the battery Positive post.

All of the above ideally should be less than 0.1 V and hopefully less than 0.2 V.

The alternator 3-pin connector that you replaced has three wires. The middle one goes to the battery positive post (among other connections) through a fuse, # 3 (10 Amps) in the main engine compartment fuse box. (I'm using the 2002 model as my reference; there's a chance another year could be different, even within the 2000-2004 generation. Perhaps include the model year.) This is the alternator's "sense" connection which is used to determine the state of charge of the battery and the overall electrical system voltage. If the system voltage is low, the alternator output is increased and vice-versa. So this connection is rather important. With the engine turned off, check the voltage between that pin (middle, # 2) and ground. (Back-probe the connector.) It should be the same as the voltage between the battery posts. Start the engine; it should rise to the higher battery voltage when the engine is running.

With the engine off, disconnect the three pin connector at the alternator. Turn the ignition switch to ON. Does the battery warning light come on? (It shouldn't, but this will check for a short or partial short in the wiring between the light and pin 1 of the alternator connector that could cause the light to remain on.)

There's one more measurement that could be made; the voltage at the third pin of the connector, which goes to the ECM. This isn't a DC voltage; rather, it's a pulsed signal which would be read as an average by most DC volt meters. It would be somewhere between 1 V and the battery voltage when measured with the engine OFF, but ignition switch at ON.

As noted, the battery warning light will come on when the voltage output of the alternator differs significantly from the voltage in the rest of the electrical system. The measurements suggested above might reveal a cause of that difference.
 

·
Registered
Joined
·
23 Posts
Discussion Starter #16
amazin information that im anxious to go troubleshoot with. im at work until 1530 today but im off all evening. ill try what you suggested and get back with some values. thanks again!
 

·
Registered
Joined
·
23 Posts
Discussion Starter #17
so I feel like an idiot testing voltages and swapping alternators.. fuse 10 was blown. replaced it and all is well. bat/alt light is off. I took 1 voltage reading at the battery posts at idle in 16 degree weather, 14.8 volts and the car wasn't warmed up. thank you plain OM for your help and everyone else who shed light on my problem.
 

·
On the Super Mod Squad
2002 3.0 VDC Wag + 2018 2.5 Leg Ltd
Joined
·
26,307 Posts
so I feel like an idiot testing voltages and swapping alternators.. fuse 10 was blown. replaced it and all is well. bat/alt light is off. I took 1 voltage reading at the battery posts at idle in 16 degree weather, 14.8 volts and the car wasn't warmed up. thank you plain OM for your help and everyone else who shed light on my problem.
fuse 10?

= under the dash that is listed for the "trailer"

and under the hood it is for the "headlight right side"

well they say 2002 and newer cars are wired together even more for a harmonious electrical system. glad you found the source of the problem.:claphead:
 

·
Registered
Joined
·
18,285 Posts
Thanks eagleeye

My error. I doubled the "10s" in post # 15. It's a 10 Amp fuse, but the fuse number is actually 3.

Here's the wiring diagram, with the sense line, and fuse, highlighted. The fuse serves only that one purpose. Fuse location shown in second diagram below (note: there's no fuse #10).



 

Attachments

·
Registered
Joined
·
23 Posts
Discussion Starter #20
sorry its not fuse # 10 its a 10 amp fuse for the alt under the hood. rotors, pads, and tires are next on the to do list this February.
 
1 - 20 of 25 Posts
Top