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Weird brake light operation (video)

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3 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis

THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCHWeird brake light operation (video)

Leading reported evidence

Install tail light assembly (driver's side)

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
I just installed a new tail light assembly (driver's side), using my existing bulbs.
Original post Read captured discussion
Weird brake light operation (video)

Frequently discussed work

Check lights operation i noticed something weird

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
Went to check the lights operation I noticed something weird.
Original post Read captured discussion
Weird brake light operation (video)

Read full discussion summary

Leading evidence: 'Install tail light assembly (driver's side)' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check lights operation i noticed something weird' (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.

Read captured replies

1 matching discussions · 3 captured posts examined · 0 partial discussions

Compare 3 other evidence results

Check lights operation i noticed something weird

Suggestion or failed attempt

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
Went to check the lights operation I noticed something weird.
Original post Read captured discussion
Weird brake light operation (video)

Replace bulbs

Suggestion or failed attempt

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 might as well replace bulbs on both side, since when one goes, the other one if likely not too far behind.
Original post Read captured discussion
Weird brake light operation (video)

Use existing bulbs

Suggestion or failed attempt

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
I just installed a new tail light assembly (driver's side), using my existing bulbs.
Original post Read captured discussion
Weird brake light operation (video)

Frequently discussed actions (4)

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

Check lights operation i noticed something weird

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
Went to check the lights operation I noticed something weird.
Original post Read captured discussion
Weird brake light operation (video)

Install tail light assembly (driver's side)

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 · Original poster
I just installed a new tail light assembly (driver's side), using my existing bulbs.
Original post Read captured discussion
Weird brake light operation (video)

Replace bulbs

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 might as well replace bulbs on both side, since when one goes, the other one if likely not too far behind.
Original post Read captured discussion
Weird brake light operation (video)

Use existing bulbs

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
I just installed a new tail light assembly (driver's side), using my existing bulbs.
Original post Read captured discussion
Weird brake light operation (video)

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.

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

Rennlist: 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: 20261026T083035Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Hey guys, I just installed a new tail light assembly (driver's side), using my existing bulbs. Went to check the lights operation I noticed something weird. The main brake light bulb seems to work (21w?), but the running light function doesn't work for the same bulb (5w?). I seem to remember something about European safety feature about just one fog light working, but not sure if that's what I'm seeing. Poll: 1. Do I just need to order a new bulb (21w/5w)? 2. Maybe previous owner installed wrong bulb (21w only)? 3. Did I brake a wire while switching tail lights? 4. Is this normal? Thanks for the help! Chris 2002 Porsche 911 Targa brake light operation - YouTube

POST 2 / ORIGINAL POSTEROriginal post

Looks like the replacement bulb is 21w/5w dual filament, so maybe just the 5w filament burnt out? I believe its part number 900 631 128 90.

POST 3Original post

Quotes source post: 10759854

Yep, just go to the local auto parts store and they will have a cross reference catalog for you to find the right type of bulbs, I just went through the exercise a couple of weeks ago. You don't need to go with Porsche part numbers. You might as well replace bulbs on both side, since when one goes, the other one if likely not too far behind. FWIW, the Euro rear fog light lights up on the left side tail light only, you will see it once you take the housing off and see where the harness goes.

This is a source reference. Confirm exact model applicability in the original material.