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08 Box Base Alternator - 986 Forum - The Community for Porsche Boxster & Cayman Owners

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6 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCH08 Box Base Alternator - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Leading reported evidence

Clean with a rebuild kit

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

A rebuilt is usually your old one cleaned with a rebuild kit on so it will be about competency and wallet size at this point.

08 Box Base Alternator - 986 Forum - The Community for Porsche Boxster & Cayman Owners
Frequently discussed work

Check connections and ground

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster

Will check connections and ground.

08 Box Base Alternator - 986 Forum - The Community for Porsche Boxster & Cayman Owners
Read full discussion summary

Leading evidence: 'Clean with a rebuild kit' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check connections and ground' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.

Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.

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1 matching discussions · 6 captured posts examined · 0 partial discussions

Compare 4 other evidence results

Replace alternator

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

I wouldn’t change the battery until I recharged it and swapped the alternator.

08 Box Base Alternator - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Test good ...but ....it wasn't the correct battery

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed · Original poster

Ok...Battery tested good ...but ....it wasn't the correct battery for the car so I dropped in a new one.

08 Box Base Alternator - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Check connections and ground

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster

Will check connections and ground.

08 Box Base Alternator - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace battery until i recharged it and swapped the alternator

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

I wouldn’t change the battery until I recharged it and swapped the alternator.

08 Box Base Alternator - 986 Forum - The Community for Porsche Boxster & Cayman Owners
Frequently discussed actions (10)

These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.

Check connections and ground

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster

Will check connections and ground.

08 Box Base Alternator - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Clean with a rebuild kit

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

A rebuilt is usually your old one cleaned with a rebuild kit on so it will be about competency and wallet size at this point.

08 Box Base Alternator - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace alternator

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

I wouldn’t change the battery until I recharged it and swapped the alternator.

08 Box Base Alternator - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace battery until i recharged it and swapped the alternator

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

I wouldn’t change the battery until I recharged it and swapped the alternator.

08 Box Base Alternator - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Run engine

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster

Did an Alternator test by attaching multimeter to battery w/ running engine.

08 Box Base Alternator - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Test alternator

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

If your going to test the alternator, test it at the alternator not the battery.

08 Box Base Alternator - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Test alternator start at the alternator, if it tests good

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

If you want to test the alternator start at the alternator, if it tests good then do a voltage drop test at each wiring connection.

08 Box Base Alternator - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Test automotive charging systems

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

Or google testing automotive charging systems.

08 Box Base Alternator - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Test automotive charging systems, also how

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

You have a multi meter, go to youtube and watch how to test automotive charging systems, also how to do voltage drop tests.

08 Box Base Alternator - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Test by attaching multimeter

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster

Did an Alternator test by attaching multimeter to battery w/ running engine.

08 Box Base Alternator - 986 Forum - The Community for Porsche Boxster & Cayman Owners
Coverage and how to read this overview

Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.

6 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.

  • 986Forum: 1 discussions

0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.

0 acknowledgements have no verified action link; they do not establish a repair result.

Generation: 20261026T222516Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Did an Alternator test by attaching multimeter to battery w/ running engine. Read 12 volts then fell to 10.5. Battery not holding a charge as well. I assume both batt and alternator are toast. Thoughts ? V

POST 2Original post

Even if the battery was toast the alternator would still push 13.5-14v. The regulator/rectifier is shot but now a days you can’t just buy parts, just swap components. I wouldn’t change the battery until I recharged it and swapped the alternator. The battery can only accept what it’s given. If your alt is only putting out 10.5 the battery will never be more that 10.5

POST 3Original post

If your going to test the alternator, test it at the alternator not the battery. You could simply have a bad or dirty connection at the battery, ground points, or connections at the alternator or faulty, damaged wiring. If you want to test the alternator start at the alternator, if it tests good then do a voltage drop test at each wiring connection. Work you way to the battery. If the alternator is in fact faulty replace it. Then do a voltage drop test at the battery cable connections. If you have voltage drop then find the bad connection or wiring by doing voltage drop tests on the wiring and wiring connections from the alternator to the battery. If no voltage drop then charge the battery and have it load tested. By testing this way the entire charging system is tested and proven good or faulty and the faults are found and corrected. The way your testing you could conclude that the alternator is bad when it could just be a dirty or loose wiring connection. Spendy mistake. You have a multi meter, go to youtube and watch how to test automotive charging systems, also how to do voltage drop tests. Or google testing automotive charging systems. Also how to perform voltage drop tests.

POST 4 / ORIGINAL POSTEROriginal post

Ok...Battery tested good ...but ....it wasn't the correct battery for the car so I dropped in a new one. Measured voltage across terminals w/ engine running and got around 10.5 volts. I assume its the alternator or voltage regulator. Will check connections and ground. Any thoughts. Thanks V

POST 5Original post

Check the voltage as you start, pre starting it should read high 11, low 12. Drop when starting abd then 13+ and settle at 12+. 10.5v I assume is the voltage when not running also. If the voltage does not move above static charge then the alternator is putting nothing out. The car does not care what battery it has. Getting to the alternator is pretty easy and a rebuild kit is about $60 from Bosch (you can get a cheaper brush only kit, I don’t know if it’s worth cheaping out here, I’ve done it with crank sensors and was nothing but trouble), of throw a rebuilt one in. A rebuilt is usually your old one cleaned with a rebuild kit on so it will be about competency and wallet size at this point. If you are just buying batteries off the shelf I’m assuming you are looking for the fastest option, if so a rebuilt one may be the quick abd easy option with regards to availability. https://www.pelicanparts.com/techarticles/Boxster_Tech/82-ELEC-Alternator/82-ELEC-Alternator.htm Alternator parts number for 2008 base 986 99760302204 cross references with 99760302200 99760302202 AL0869N A quick glance shows https://www.maniacelectricmotors.com/alternator-rebuild-kit-for-porsch-911-carrera-0124525106-0124525107.html But says aftermarket brush kit but does cross reference part numbers to F00M145651 And a search with that part number brings up seller CSS on eBay who I have gotten many parts from. I include numbers for people who may be searching later and the links may well be expired by then.

POST 6 / ORIGINAL POSTEROriginal post

No it was 10.5v when running. I'm assuming alternator is dead. Any issue using aftermarket rebuilt alts such as ac Delco? ******************************** offers them at pretty good price. Thanks for reply. V

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