Jump to content


Welcome to Ultimate Subaru Message Board, my lurker friend!

Welcome to Ultimate Subaru Message Board, an unparalleled Subaru community full of the greatest Subaru gurus and modders on the planet! We offer technical information and discussion about all things Subaru, the best and most popular all wheel drive vehicles ever created.

We offer all this information for free to everyone, even lurkers like you! All we ask in return is that you sign up and give back some of what you get out - without our awesome registered users none of this would be possible! Plus, you get way more great stuff as a member! Lurk to lose, participate to WIN*!
  • Say hello and join the conversation
  • Subscribe to topics and forums to get automatic updates
  • Get your own profile and make new friends
  • Classifieds with all sorts of Subaru goodies
  • Photo hosting in our gallery
  • Meet other cool people with cool cars
Seriously, what are you waiting for? Make your life more fulfilling and join today! You and your Subaru won't regret it, we guarantee** it.

* The joy of participation and being generally awesome constitutes winning
** Not an actual guarantee, but seriously, you probably won't regret it!

Serving the Subaru Community since May 18th, 1998!

Guest Message by DevFuse
 

Photo
- - - - -

No battery light/ dead alternator?


  • Please log in to reply
22 replies to this topic

#1 coolskaterkid

coolskaterkid

    USMB Regular

  • Members
  • 141 posts
  • south lake tahoe

Posted 20 December 2012 - 09:00 PM

So driving home today, i thought the dash lights looked dim, and a couple seconds later the radio cut out, so turned off all electronics except headlights and barley made it home. tried to start it and just a click, but no battery light went on. But now when just turning the key to on, i have no battery light, it usually lights when the key is on and goes out once started. Last time the alternator died it did the same thing no battery light while going down the road, but it did show when the key was on. So since its not lighting now do i have a different issue?

#2 Rooster2

Rooster2

    Subaru Master

  • Members
  • 3,345 posts
  • Indianapolis

Posted 20 December 2012 - 10:14 PM

In my experience, a battery light indicates that the alternator is not charging the battery. However, from what you describe of the lights going dim, and radio going out, it sounds like an alternator problem, so go figure??

Suggest you charge your battery, then drive to an auto parts store. At no charge to you, a counter guy will test your car's battery, and charging system in their parking lot with their tester system. They should definitely tell you what is wrong.

#3 coolskaterkid

coolskaterkid

    USMB Regular

  • Members
  • 141 posts
  • south lake tahoe

Posted 20 December 2012 - 10:19 PM

So far charged the battery,got out the multi-meter and it sits at 12.60v, when started dropped to 12.0 and kept dropping at idle. So defiantly no charge, but no battery light at all, even on the bulb test before start. I thought on some cars it uses the battery light bulb to complete the charging circuit, hopefully not the case here

#4 Gloyale

Gloyale

    It's a sickness

  • Members
  • 8,560 posts
  • Corvallis, OR PNW

Posted 20 December 2012 - 10:25 PM

burnt out bulb.

Won't charge properly without it for field.

#5 89Ru

89Ru

    Eat, Live, Breath Subaru

  • Members
  • 357 posts
  • Nashville TN

Posted 20 December 2012 - 10:32 PM

what are you driving?

sounds like you are on the second alternator already. aftermarket alternator? search the board for a subaru remanufactured alternator if you need to replace it again.

should be a direct connection to the battery from the alternator (through a fusible link). you can check voltages at the alternator also.

how new is the battery? if more than 5-6 years replace it. problems with the battery could lead to alternator failures.

Edited by 89Ru, 20 December 2012 - 10:36 PM.


#6 coolskaterkid

coolskaterkid

    USMB Regular

  • Members
  • 141 posts
  • south lake tahoe

Posted 20 December 2012 - 10:45 PM

what are you driving?

sounds like you are on the second alternator already. aftermarket alternator? search the board for a subaru remanufactured alternator if you need to replace it again.

should be a direct connection to the battery from the alternator (through a fusible link). you can check voltages at the alternator also.

how new is the battery? if more than 5-6 years replace it. problems with the battery could lead to alternator failures.



Completely forgot, its a 93 legacy auto.

First alternator went around 180k, this one i grabbed from a junk yard, car had that had around 120k on it, my cars got 212k on it now, battery only a year old, if not less. So sounds like ill be ripping apart the dash to replace the bulb, doesnt sound like fun. With 5 feet of snow expected over the next three days. Thanks will get alt tested at parts store any ways. Also replace bulb and will report back
Edit: any one have a guide to removing the gauge cluster?

Edited by coolskaterkid, 20 December 2012 - 11:23 PM.


#7 89Ru

89Ru

    Eat, Live, Breath Subaru

  • Members
  • 357 posts
  • Nashville TN

Posted 20 December 2012 - 11:22 PM

burnt out bulb.

Won't charge properly without it for field.


Didn't know that. Looking through wiring diagrams from 1992 legacy. Alternator charge output and battery positive are connected through fusible link. ALT-1 trace goes from the alternator to the dash CHARGE lamp and is fused to battery via the ignition switch. This makes sense, there is feedback to perhaps regulate the battery charging rate. So if the bulb is burned out no alternator output. Is this the same for newer designs? There is also an ALT-2 trace that goes...not sure where.

#8 Gloyale

Gloyale

    It's a sickness

  • Members
  • 8,560 posts
  • Corvallis, OR PNW

Posted 21 December 2012 - 06:59 PM

Didn't know that. Looking through wiring diagrams from 1992 legacy. Alternator charge output and battery positive are connected through fusible link. ALT-1 trace goes from the alternator to the dash CHARGE lamp and is fused to battery via the ignition switch. This makes sense, there is feedback to perhaps regulate the battery charging rate. So if the bulb is burned out no alternator output. Is this the same for newer designs? There is also an ALT-2 trace that goes...not sure where.


Charge light excites the field.

Alt-2 circuit is tied to Ig. circuit to ECU through a diode.....some sort of self shutoff, and this Switched 12v is the reference voltage for alt output.

newer models no ALT-2, charge light does it all.

#9 coolskaterkid

coolskaterkid

    USMB Regular

  • Members
  • 141 posts
  • south lake tahoe

Posted 21 December 2012 - 09:56 PM

Took gauge cluster out, removed bulb and switched with the oil pressure bulb, and still no light, but light lit the oil pressure. So bulb is fine, took alt to auto parts store, and tests good. Where do i look next?

#10 Gloyale

Gloyale

    It's a sickness

  • Members
  • 8,560 posts
  • Corvallis, OR PNW

Posted 21 December 2012 - 10:12 PM

Took gauge cluster out, removed bulb and switched with the oil pressure bulb, and still no light, but light lit the oil pressure. So bulb is fine, took alt to auto parts store, and tests good. Where do i look next?


Have you checked the 10 amp "charge" fuse in the fusebox?

#11 coolskaterkid

coolskaterkid

    USMB Regular

  • Members
  • 141 posts
  • south lake tahoe

Posted 21 December 2012 - 10:27 PM

Have you checked the 10 amp "charge" fuse in the fusebox?


Did not find any fuse labeled "charge" in both the inside fuse box or main fuse box under hood. But checked all fuses with my fuse tester, and all tested good

Edited by coolskaterkid, 21 December 2012 - 10:32 PM.


#12 Gloyale

Gloyale

    It's a sickness

  • Members
  • 8,560 posts
  • Corvallis, OR PNW

Posted 21 December 2012 - 10:38 PM

Did not find any fuse labeled "charge" in both the inside fuse box or main fuse box under hood. But checked all fuses with my fuse tester, and all tested good


Fuse # 15, 10 amp. in the inside fuse box

Also inspect the connection of the White/red wire at the alt (smallest)<<<<<<OOPS!!! I'm thinking EA here.

test the bulb by turning key on, and grounding out the white/red wire....this should light the bulb. If it does, the system is fine and the culprit is the ALT. If not....problem in circuit (fuses, bulb out, wire disconnected)

EJ The car in question here uses a Black/white wire for "charge" light. Larger gauge than the yellow wire

Edited by Gloyale, 22 December 2012 - 01:10 PM.
Correction of wire color


#13 coolskaterkid

coolskaterkid

    USMB Regular

  • Members
  • 141 posts
  • south lake tahoe

Posted 21 December 2012 - 10:49 PM

Fuse # 15, 10 amp. in the inside fuse box

All ten amp fuses inside car are fine.

#14 Fairtax4me

Fairtax4me

    Su bah roo'n

  • Gold Subscribers
  • 7,884 posts
  • Charlottesburg, VA

Posted 21 December 2012 - 11:15 PM

Did you remove the fuses to test them? If not how did you test them? Resistance? Test light? Neither will tell you if this fuse is blown. Resistance can be checked only by removing the fuse.

Fuses good and the bulb works, check circuit operation as Gloyale said, ground the small white/red wire with the key On.

#15 coolskaterkid

coolskaterkid

    USMB Regular

  • Members
  • 141 posts
  • south lake tahoe

Posted 21 December 2012 - 11:21 PM

Did you remove the fuses to test them? If not how did you test them? Resistance? Test light? Neither will tell you if this fuse is blown. Resistance can be checked only by removing the fuse.

Fuses good and the bulb works, check circuit operation as Gloyale said, ground the small white/red wire with the key On.


Used buss brand fuse tester, how would i ground the wire? just unplug the connector and run a jumper from that wires pin to body ground?

Edited by coolskaterkid, 21 December 2012 - 11:25 PM.


#16 89Ru

89Ru

    Eat, Live, Breath Subaru

  • Members
  • 357 posts
  • Nashville TN

Posted 22 December 2012 - 12:04 AM

yes, disconnect from the alternator and run a wire to the (-) battery terminal.

my diagram shows a black/white wire for some reason for the ALT-1 wire at the alternator connector. solid white wire is tied to ALT output, don't use that wire.
with ignition on (car not running) you should have 12 volts on that wire before grounding it. if you don't, there are problems upstream. in that case, check SBF's 3,4,5 in the main fuse box under the hood.

this will test a few things.
1. battery is supplying voltage via fuse #15 to the charge lamp in the dash
2. charge lamp and wiring is good all the way to the alternator
3. 45 amp fuses are good upstream towards the battery

these drawings are from 1997 EJ but the ALT-1 wire colors are the same as 1992.

Posted Image

Posted Image

Edited by 89Ru, 22 December 2012 - 02:22 PM.
Add year of schematic


#17 Gloyale

Gloyale

    It's a sickness

  • Members
  • 8,560 posts
  • Corvallis, OR PNW

Posted 22 December 2012 - 01:15 PM

Used buss brand fuse tester, how would i ground the wire? just unplug the connector and run a jumper from that wires pin to body ground?



See above for wire color correction


Yup, pull the connector, insert a jumper into the Black/white wire in the connector and run it to ground. Turn key to on, and see if the charge light comes on.

89ru, that is a newer model ALT diagram......although the Charge light, "ALT 1" circuit is essentially the same. Same fuse #15 supplies power to dash warning lights.

#18 89Ru

89Ru

    Eat, Live, Breath Subaru

  • Members
  • 357 posts
  • Nashville TN

Posted 22 December 2012 - 02:11 PM

Gloyale: You caught me. Here's the earlier version from 1992. ALT-1 circuit is the same as you said.

Posted Image

#19 coolskaterkid

coolskaterkid

    USMB Regular

  • Members
  • 141 posts
  • south lake tahoe

Posted 22 December 2012 - 11:18 PM

So tested it as shown and the light comes on, so alternator after all.Im going to tell auto zone there alt tester sucks. What makes them fail this way, the last time it did the same thing, no warning light, and once i noticed it was to late resulting in towing it home. Also some one said somthing about getting a alternator straight from subaru. Are they better then the parts stores, or cheaper maybe?

Edited by coolskaterkid, 22 December 2012 - 11:22 PM.


#20 edrach

edrach

    Charter member OFRT

  • Members
  • 12,324 posts
  • Bothell, WA

Posted 22 December 2012 - 11:29 PM

So tested it as shown and the light comes on, so alternator after all.Im going to tell auto zone there alt tester sucks. What makes them fail this way, the last time it did the same thing, no warning light, and once i noticed it was to late resulting in towing it home. Also some one said somthing about getting a alternator straight from subaru. Are they better then the parts stores, or cheaper maybe?

Maybe better, but certainly not cheaper. I have quite a few wrecking yard alternators for the EJ22 series (my '97 Impreza). Whenever I see a good one at Pull a Part, I buy it and install it on my Impreza. The old alternator gets marked "used but tested good." And the new one stays on until it fails or is replaced by another. If your car uses the same alternator (check the large plug...the shape will tell you which version you have), I'd be glad to ship you one of my "tested" ones. If I have to ship, $45 would include the alternator as well as the shipping.

#21 Fairtax4me

Fairtax4me

    Su bah roo'n

  • Gold Subscribers
  • 7,884 posts
  • Charlottesburg, VA

Posted 23 December 2012 - 02:33 AM

95-99 alternators had a recall so Subaru sells reman units for about $75.
You could put one of these in your car but you need to swap the wire harness connector to match.
I suppose you could also just use spade terminals, but it won't be waterproof.

So tested it as shown and the light comes on, so alternator after all.

Check resistance on the lead that goes from the alternator to the fuse panel just to make sure it's not all corroded inside. Should be little or no resistance.
Also worth checking voltage at the alternator output with the engine running.

Edited by Fairtax4me, 23 December 2012 - 02:43 AM.


#22 edrach

edrach

    Charter member OFRT

  • Members
  • 12,324 posts
  • Bothell, WA

Posted 23 December 2012 - 11:09 AM

Also worth checking voltage at the alternator output with the engine running.

Easiest check to see if the alternator is working like it should: At idle you should see around 12.5 to 13 volts dc; run the rpm up and the output should increase to 13.5 to 14 volts at 3000 rpm. With more rpm the max volts should hold steady; anything above 15 volts at high rpm indicates a faulty internal voltage regulator. A better test is to do this with the headlights on; loading down the alternator shouldn't affect the output much until you reach the maximum load rating (around 65 amps for the early alternators). I usually duplicate the readings at the battery terminals (should be the same).

#23 coolskaterkid

coolskaterkid

    USMB Regular

  • Members
  • 141 posts
  • south lake tahoe

Posted 31 December 2012 - 10:42 PM

Ended up getting an auto zone alternator, didnt have time to get to junk yard, all seemed well for about ten miles, then the battery light, and brake light started lighting up, on and off, but i thought it was odd because when the battery light came on the lights seemed to get brighter.

So i figured the regulator in it was bad, drove it from work to auto zone, and they said it had to test bad to get a replacement, but the tester on my battery car not running, and it had almost 15 volts, so it cooked my battery, the guy tried to sell me a battery for 125 bucks. But offered me ten percent off for the trouble. I talked to the manager and ended up getting the battery for 35 bucks, and the second alternator seems to be working fine. Wont ever get a parts store alternator again what a pain

Thanks everyone for helping me diagnose the issue.




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users