Subaru Outback Forums banner

97 Legacy Outback fried 2 new alternators...so far

61K views 46 replies 11 participants last post by  8kGoodENuff 
#1 ·
OK - I'm at my wit's end! Please excuse this lengthy explanation in advance - here's the story:

Just bought our first Subaru ever - 1997 Legacy Outback 2.5L with 185K miles - from a used car lot. The dealer had a local shop go over it to make sure there were no "big" problems. Everything seemed to work fine, just some cosmetic flaws from a baseball-size hailstorm we had here at the end of June. (The perfect car for my teenage son to drive.)

Within a week, he started having to jump-start it almost every time he stopped somewhere. After some messing around at home, we jumped it and took it to a parts store for a free charging system check. They said the battery was fine (just a bit low), but there was no charging voltage out of the alternator.

So we bought a "new" remanufactured alternator from our local Subaru dealer and installed it. I don't think we checked the alternator output / charging voltage right away - we stupidly assumed that the problem was fixed. Ha! Within a week, again, my son was having to jump-start the car every time he stopped anywhere. (Luckily, we live where everyone's a Good Samaritan and it's easy to get help.)

We thought maybe the battery was just too deeply discharged for the alternator to recharge it during his quick trips around town. So we put the battery on a trickle charger overnight, put it back on the car the next morning, and sent him off to school. After just a few trips around town, the battery was dying again. We spent a couple of weeks screwing around with it again - checking connections, ground continuity, etc. Finally took it to have a battery check again and got the same story - battery was fine, alternator was not charging. This time we decided to make sure it was a bad alternator - we took it out of the car and had the local NAPA store bench-test it for us. Result = no DC charging voltage = bad alternator.

So we took the "new" alternator back to the Subie dealer and did a warranty swap for another "new" alternator. We stopped on the way home and had it bench-tested at NAPA just to make sure it was good - according to their test, it was. We installed it last night, turned the car on, checked the charging voltage, and NO CHARGING VOLTAGE AGAIN!!!

I have checked and double-checked every ground connection in the engine compartment - all fine. I have tested the continuity on the battery to alternator cable - it's fine. I checked for a short between the two contacts on the alternator harness/connector - not even a highly-resistive short. I have checked the voltages on the alternator connector with the key switched on (engine not running) and get about 12V across the board - same as battery - normal, I think? But when the engine is running, the alternator output to the battery reads the same voltage as the battery (slightly lower than it tested right before I started the engine) - between 12.2 and 12.8V, depending on how many times I've started it since the battery was charged - and it's dropping.

The battery / charge indicator light (and all other idiot lights) comes on when the key is switched on and immediately goes off when the car starts, as if there's nothing wrong with the charging circuit. The CEL has come on a couple of times over the past month, but just for a short time and then goes back off. (It has also been reset repeatedly from disconnecting the battery for charging.)

HELP!
 
See less See more
#28 ·
i recently purchased a 98 outback that has various electrical issues (had a surge from VR).

long story short: PO had a shop replace alternator, but the car was still not charging. i got the car without an alternator, put a new one in-- not charging-- after inspecting grounds etc, it turned out to be the charging system indicator (battery) light in the gauge cluster was burnt out (along with a few others).

i wouldn't believe it if i didn't witness it with my own eyes, but that bulb being bad prevents the alternator from charging.

THANKS TO "plain OM"!
 
#30 ·
3. Idle with lights on while stopped at a traffic light (brake lights on) = 11.6 - 12.1V = This can't be normal. Voltage drops so low that all lights (outside and inside) dim down due to lack of voltage.
4. In items #2 & #3... once I start driving (anything over 1000 RPM), voltage goes up to 13.8 - 14.2V
The Voltage appears low when idling but could depend on where you're measuring it. If at the battery, then yes, it is low. But if at an accessory power outlet (cigarette lighter) socket, then possibly not.

Took some resistance readings:
1. Batt Neg Terminal/Chassis ground by left headlight (LHL) to chassis ground on shock mounts = 1.5 Ohms
2. Chassis Ground (LHL) to alternator = 25-30 ohms
3. Chassis Ground (LHL) to Starter Ground = 30-40 ohms
4. Chassis Ground (LHL) to Starter Ground with headlights on = 88-90 ohms

Don't those resistance readings seem kind of high?
Yes, very high. The resistance between the battery negative post and the car chassis, the engine block, or the alternator case, should all be very low. But making resistance measurements can be problematic because it depends on how good a connection the test probe makes with the test surface. For example, the 25 Ohm resistance between the alternator case and chassis ground would suggest the alternator is effectively disconnected from the rest of the car.

A better test is to measure the Voltage between the battery negative post and the other points with the engine running at around 1000 rpm and some lights on. As noted in the quote above, the measurements should be down to just a few tenths of a Volt; any more, such as the reported 1.9 Volts, indicates a problem.

4. Chassis Ground (LHL) to Starter Ground with headlights on = 88-90 ohms
This is probably an invalid reading. Resistance cannot be measured when the car is running because any Voltage between the same points will cause most multi-meters, when on a resistance range, to read incorrectly if not also be damaged by the Voltage. If all the resistance readings were done with the engine running, then they're not much use.

I show 0.0V across all points that you had measured.
Something isn't right here. If the resistance between the alternator case and the chassis ground is 25 Ohms, I would expect that with the engine running at around 1000 rpm and some lights on, the Voltage between the alternator case and the battery negative post would be high, yet you report 0.0 Volts.

What type of multi-meter are you using? Is it able to read very low voltages? If it is, are you sure it was on the lowest range when you measured 0.0 Volts?

is the engine ground the same ground as the Starter Ground? I looked for others but couldn't find any... I'm assuming that's the one considering it has the grounding cable directly attached to the battery negative terminal.
The starter ground is its case. The case is (or should be) in direct contact with the engine block. both through metal surfaces that are against each other and the bolts holding them together, so the engine ground and the starter ground should be the same.
 
#31 ·
The Voltage appears low when idling but could depend on where you're measuring it. If at the battery, then yes, it is low. But if at an accessory power outlet (cigarette lighter) socket, then possibly not.



Yes, very high. The resistance between the battery negative post and the car chassis, the engine block, or the alternator case, should all be very low. But making resistance measurements can be problematic because it depends on how good a connection the test probe makes with the test surface. For example, the 25 Ohm resistance between the alternator case and chassis ground would suggest the alternator is effectively disconnected from the rest of the car.

A better test is to measure the Voltage between the battery negative post and the other points with the engine running at around 1000 rpm and some lights on. As noted in the quote above, the measurements should be down to just a few tenths of a Volt; any more, such as the reported 1.9 Volts, indicates a problem.



This is probably an invalid reading. Resistance cannot be measured when the car is running because any Voltage between the same points will cause most multi-meters, when on a resistance range, to read incorrectly if not also be damaged by the Voltage. If all the resistance readings were done with the engine running, then they're not much use.



Something isn't right here. If the resistance between the alternator case and the chassis ground is 25 Ohms, I would expect that with the engine running at around 1000 rpm and some lights on, the Voltage between the alternator case and the battery negative post would be high, yet you report 0.0 Volts.

What type of multi-meter are you using? Is it able to read very low voltages? If it is, are you sure it was on the lowest range when you measured 0.0 Volts?



The starter ground is its case. The case is (or should be) in direct contact with the engine block. both through metal surfaces that are against each other and the bolts holding them together, so the engine ground and the starter ground should be the same.
Sorry I've taken so long to answer... I have been waiting for my new meter to arrive. I still need to double check all as you stated above.

Voltage is read via a Scan Gauge II that I have mounted over my steering wheel column. I haven't physically checked the voltage since I find the SGII to be reliable, but I should check it again and will. Evidence that verifies it is true is that all lights dim down when stopped at a light at night and when I accelerate, everything lights up normally.

You are absolutely right about taking resistance readings while the car is running. I actually got a little upset with myself in forgetting that. I will take resistance readings again and voltage readings.
**Note: Another thing you are correct about is the type of meter used. I used a meter that is used more for 120V and up and the smallest range it had to select from was 0-200V, which is too big of a range which would explain the 0.0V. That being said, that is why I ordered a new meter specfically for automotive and low voltage use.

Ok... that's what I thought about the engine ground. I looked everywhere and the only place that I could think that the engine would be grounded through would be through the starter grounding point, which has a grounding cable that runs straight to the negative batter post.

Once I have all readings again, I will repost.

Thank you again for the reply.

Andre
 
#32 ·
I looked everywhere and the only place that I could think that the engine would be grounded through would be through the starter grounding point, which has a grounding cable that runs straight to the negative batter post.
In addition, there might be one or more braided strap grounding wires between the engine block and the chassis (body) of the car.

Voltage is read via a Scan Gauge II
The ScanGauge and the lights are showing the same symptom, that is, the dropping voltage. However, if there are bad connections in the electrical system, it's quite possible that the alternator is working properly and delivering, say, 13+ Volts, and that if you were to measure Voltage at the battery posts, or at the alternator, it too would show a good Voltage, yet the ScanGauge would still be showing the drop in Voltage. This could happen if the ScanGauge is actually indicating the Voltage at some point distant from the alternator and battery and there are bad connections in between. In this case, some of the Voltage is being dropped across the bad connections, so that at the point that the ScanGauge is indicating the Voltage and the lights are connected, the Voltage is lower. In other words, the ScanGauge indication could be correct, but only for the point in the system at which it is monitoring/indicating the Voltage. I would recommend using your Voltmeter to also check the Voltage at the battery and at the alternator.
 
#33 ·
I finally took the readings... I know it's been a while but was busy with wedding preparations. As soon as I get my hands on the readings, I will post them up.

As far as the scan gauge sampling point... You could be right, but not only do the headlights dim, but also the interior lights and if I hit the mist function for the window wipers while stopped, they hardly have any power to clean the windows... Very odd. I'll post up the results but I feel the alternator is not up to standard during idling conditions at low RPM.

Andre
 
#34 ·
Ok... the results:

Resistance (car OFF) / Voltage (car ON):
Chassis Ground to:
Batt Neg Terminal = 0.0 / 18 mV
Alternator Body = 0.0 / 35 mV
Left Shock Ground = 0.4 / 3 mV
Right Shock Ground = 0.2 / 0.0 mV
Starter Ground = 0.0 / 30 mV

Batt Neg Terminal to:
Alternator Body = 0.0 / 17 mV
Left Shock Ground = 0.4 / 20 mV
Right Shock Ground = 0.6 / 20 mV
Starter Ground = 0.0 / 10 mV

Voltage (car OFF):
Batt Pos Terminal to Batt Neg Terminal & All Grounds = 12.62 V

Chassis Ground to All Grounds = 0.0 V

Voltage (car ON & lights OFF):
Batt Pos Terminal to Batt Neg Terminal & All Grounds = 13.8 V

Voltage (car ON & lights ON):
Batt Pos Terminal to Batt Neg Terminal & All Grounds = 12.1 V

The only thing that I can gather from this is that the grounding points seem to be fine. They all have acceptable results but yet as soon as those lights come on, the voltage drop is a little ridiculous. And those last readings with the lights ON, that wasn't even with the brakes pressed (brake lights off). When at a traffic light, I see voltage drop to as low as 11.9 V. I honestly feel the alternator is the issue here, but I'm not 100% familiar with all of this, so if someone else has any ideas, please place them on the table.

Thank You,
Andre
 
#45 ·
Problem was the Alternator



I personally dislike when issues are brought up by posters and when solution is found, there is no follow up. That being said, although it's been just over 2 years, I wanted to give an update since the problem was found.

The alternator during all the readings that I was taking finally failed. Instead of going to the Autozone for a replacement, I decided to go to Subaru for a re manufactured alternator. I swapped it in 2 days ago and I no longer have a voltage problem. The lowest I've seen right now with headlights, brake lights, and HVAC fan on has been about 13.0V, where previously (even when 2 alternators were "new") I was getting about 10.9V. Also, voltage isn't jumpy at all. Maintains 14.0V very consistently where as previously, it was constantly jumping between 13.0 & 14.0V with teh car idling and no load.

Anyway, the only thing I can think of is that the batch of alternators that Autozone had were probably rebuilt at the same time and maybe all had issues. The last time I had an alternator failure, I replaced it, was no good, went back 2-3 days later, and the 2nd one was no good either. I should have went back for a 3rd one but didn't.

Anyway... all is well now, so if you have a low voltage issue, consider the alternator even though you may not be getting a battery indicator on the dask letting you know there is an issue.

Thank You.
 
#46 ·
I personally dislike when issues are brought up by posters and when solution is found, there is no follow up. That being said, although it's been just over 2 years, I wanted to give an update since the problem was found.

The alternator during all the readings that I was taking finally failed. Instead of going to the Autozone for a replacement, I decided to go to Subaru for a re manufactured alternator. I swapped it in 2 days ago and I no longer have a voltage problem. The lowest I've seen right now with headlights, brake lights, and HVAC fan on has been about 13.0V, where previously (even when 2 alternators were "new") I was getting about 10.9V. Also, voltage isn't jumpy at all. Maintains 14.0V very consistently where as previously, it was constantly jumping between 13.0 & 14.0V with teh car idling and no load.

Anyway, the only thing I can think of is that the batch of alternators that Autozone had were probably rebuilt at the same time and maybe all had issues. The last time I had an alternator failure, I replaced it, was no good, went back 2-3 days later, and the 2nd one was no good either. I should have went back for a 3rd one but didn't.

Anyway... all is well now, so if you have a low voltage issue, consider the alternator even though you may not be getting a battery indicator on the dask letting you know there is an issue.

Thank You.
If it has not been listed in this thread already:

If it comes up again, get a subaru one from the dealer. probably cheaper then the ones from any parts store, as there was a problem with the factory ones for the cars made around this period. ,...and at this late date with so few EJ25D on the road anymore they probably won't even ask you for a core.
 
#36 ·
The ground-related readings do seem to be good.

I'm more used to the "Batt Neg Terminal to:" readings being done with additional load, such as lights etc, and the engine revved up to above 1000 rpm. This increases the ground currents between the various grounds, and makes the bad connections, if there are any, more noticeable.

Another Voltage measurement would be from the battery positive post to the large cable connector (post) on the alternator. With the engine running at above idle, some lights on, the Voltage should be very low. (This would identify a bad cable between the battery positive post and the alternator post which could be caused by unseen corrosion under the insulation and crimp connectors.)

Nevertheless, the "Voltage (car ON & lights OFF):" and "Voltage (car ON & lights ON):" readings, along with the ground connection voltage readings do seem to eliminate the grounds and implicate the alternator. 12.1 Volts at the battery is too low.

Many people use parts store rebuilt alternators without problems, while others seem to face performance issues never seen with the car's original alternator. It's strange, but it does happen.

Perhaps try a rebuilt from another store that, hopefully, is from another rebuilder. Or, see if you can find an original from a recycled 98 -- it might be old, but if it works better in your car you will know that the rebuilds were not as good as they should be.
 
#38 ·
Your Owners Manual should have a diagram, or diagrams, of the instrument panel showing where the "Battery" or "Charge" warning light would appear when it's on. (It might be a word, or a diagram of a battery.) With the instrument cluster pulled out, the bulb should be directly behind where the diagram shows it.

Otherwise, do a title search for the words: instrument cluster. There should be several threads dealing with the cluster bulbs.
 
#39 ·
Hi guys,
I own Outback 2002 and after coming cold weather I got the issue: after starting COLD machine, battery and parking brake indicators on dashboard are ON during some time (10-20 minutes) and then they are OFF. Headlights should be ON automatically after engine is started, but they are OFF during the time when indicators are ON. Couple of days ago, in heavy traffic and these two indicators in ON state I got in addition ALL dashboard's indicators ON. Pushing gas pedal several times to 3000-4000RPM set all indicators to OFF state. So, it seems like alternator can't start on cold machine and started only some warm-up. Is this known issue for my model?
Previous owner had replaced alternator about year ago and I've replaced battery this September.

Thanks!
Alex
 
#42 ·
That is the exact problem that I have also. Never had the issue from spring to fall but once winter hits us, the issue begins. Start car in the cold, battery and brake light come on. In a few minutes when the car warms up, lights go out and you can hear a sound like the coolant fans starting.... but the sound is from the alternator.
 

Attachments

#40 ·
The alternator is probably failing. The other warning lights are probably coming on because the battery is being depleted and those other systems are unable to function properly.

I wouldn't say that alternator cold weather failure is a "known issue" with your car any more than it might be for any make of car. But in this case we don't know if the replacement alternator is a Subaru one, a rebuilt, or an aftermarket make. There have been reports here of parts store rebuilt and aftermarket alternators not being reliable in the longer term.

Also, as this thread demonstrates, problems with alternators and batteries might not be due to failures in those parts, but elsewhere, such as the ground connections and wires.
 
#41 ·
plain_OM, thanks for quick reply!
I've scheduled appointment for this Saturday on my mechanic's site, his first approach is replacing alternator, but I'll ask him to check all grounding/alternator connections and test result with starting cold car, because on warm engine I never saw this charging problem.
 
#43 ·
As noted earlier, the alternator is probably failing. Could be a fault in the internal regulator -- a bad joint when cold, but makes contact when it's warmed up.

The sound from the alternator could be due to the load on it -- because the car was started and driven for some time, the battery is low, and the alternator is working hard to recharge the battery.

Haven't heard back from Alex1974, so we don't yet know if the alternator was the problem in that case.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top