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996 alternator voltage regulator

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

Discussion summary

YOUR RESEARCH996 alternator voltage regulator

Leading reported evidence

Replace regulators

Performed · outcome unconfirmed

No successful repair reported for this finding.

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0
Unsuccessful attempts
1
Discussions
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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've changed regulators on my Hondas where the regulator is separate.)

996 alternator voltage regulator
Frequently discussed work

Replace alternator regardless

No successful repair reported for this finding.

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0
Unsuccessful attempts
1
Discussions
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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

Bear in mind that is not always the issue so you might end up replacing the alternator regardless .

996 alternator voltage regulator
Read full discussion summary

Leading evidence: 'Replace regulators' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'vr is' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Replace alternator regardless' (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 · 11 captured posts examined · 0 partial discussions

Compare 4 other evidence results

vr is

Suggestion or failed attempt

No successful repair reported for this finding.

0
Identified cause
1
Suspected cause
0
Reported fixes
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 suspect a cause
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.

Suspected cause · Original poster

I suspect the VR is on it's way out.

996 alternator voltage regulator

Replace alternator regardless

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

Bear in mind that is not always the issue so you might end up replacing the alternator regardless .

996 alternator voltage regulator

Replace regulator and can not be done in-situ

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

I presume the alternator needs to be removed to change the regulator and can not be done in-situ?

996 alternator voltage regulator

Replace theirs

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

Any one changes theirs?

996 alternator voltage regulator
Frequently discussed actions (7)

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

Replace alternator regardless

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

Bear in mind that is not always the issue so you might end up replacing the alternator regardless .

996 alternator voltage regulator

Replace regulator and can not be done in-situ

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 presume the alternator needs to be removed to change the regulator and can not be done in-situ?

996 alternator voltage regulator

Replace regulators

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've changed regulators on my Hondas where the regulator is separate.)

996 alternator voltage regulator

Replace theirs

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

Any one changes theirs?

996 alternator voltage regulator

Replace with revs

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

As a word of warning for everyone else, if you see your voltage start to change with revs from 11-14v, and you are 5miles from home, don't persevere, park it up and get recovered.

996 alternator voltage regulator

Use another

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've been relying on the dashboard voltmeter, I'll use another to verify the voltage under load.

996 alternator voltage regulator

Suggestion · Original poster

I've been relying on the dashboard voltmeter, I'll use another to verify the voltage under load.

996 alternator voltage regulator

Use cigarette lighter

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 don't have heated seats, so I'll use the cigarette lighter to provide the additional load.

996 alternator voltage regulator

Suggestion · Original poster

I don't have heated seats, so I'll use the cigarette lighter to provide the additional load.

996 alternator voltage regulator
Reported and suspected causes (1)

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

vr is

No successful repair reported for this finding.

0
Identified cause
1
Suspected cause
0
Reported fixes
Read evidence and context
Discussions that suspect a cause
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.

Suspected cause · Original poster

I suspect the VR is on it's way out.

996 alternator voltage regulator
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.

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

  • 911uk: 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: 20261027T000231Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

The idle voltage is around 13.4V. I've always looked out for around 14V. I suspect the VR is on it's way out. Can someone confirm the OEM part number? I've found most places say it's F00M144151, F00M144136 and others F00MA45232. Any one changes theirs? Any tips?

POST 2Original post

I bought one for the GT3 from this fella: https://www.ebay.co.uk/itm/262230318722 Worked perfectly until the alternator died from othe causes at 180K miles

POST 3 / ORIGINAL POSTEROriginal post

Thanks Nick, looks like the Bosch designation is F00M144136

POST 4Original post

Here you are, with pictures, I did mine recently. http://911uk.com/viewtopic.php?t=145619&highlight=

POST 5Original post

Great thread. My 996.2 is exactly the same, ~12v with the engine running, but because it's still in warranty I'm getting eporsch to sort it out.

POST 6Original post

To test .. Engine at operating temp .. electrical load on so lights on main beam . fog lights , hazard lights , heated seats and radio on .. If a seperate voltmeter on the battery indicates 13 volts or lower on idle then the alternator or possible wiring has an issue with the alternator being the issue 9.5 times out of ten . Above 13 and it's fine with a sensible reading of 13.3 - 13.4 . Don't use the onboard voltmeter .. it's not that accurate .

POST 7Original post

...Operating temperature - very important. Sick regulators don't like heat. my regulator would start at 14 when cold and work its way to 12 (on the dash gauge) as the engine warmed. Took me a while to notice and then Figure it out.

POST 8 / ORIGINAL POSTEROriginal post

I've been relying on the dashboard voltmeter, I'll use another to verify the voltage under load. I don't have heated seats, so I'll use the cigarette lighter to provide the additional load.

POST 9 / ORIGINAL POSTEROriginal post

I've been relying on the dashboard voltmeter, I'll use another to verify the voltage under load. I don't have heated seats, so I'll use the cigarette lighter to provide the additional load. I presume the alternator needs to be removed to change the regulator and can not be done in-situ? (I've changed regulators on my Hondas where the regulator is separate.)

POST 10Original post

Lights on main beam with fog lights on will be enough .. the main figure i work to is 13 volts and less means its an alternator on its way out .. above that and your ok but 13.4 is what i would like to see. Basically on idle this is a huge load for an alternator so any issues will show up on this test . Voltage reg replacement is an alternator out job . Bear in mind that is not always the issue so you might end up replacing the alternator regardless .

POST 11Original post

I also found the bolts attaching the regulator to the alternator very corroded, so even though I had bought a new regulator ended up replacing the whole alternator (bolts sheared, and I could support it well enough under the pillar drill to tried drilling out by hand, but steel bolt in ali I ended up damaging the housing, so new alternator). As a word of warning for everyone else, if you see your voltage start to change with revs from 11-14v, and you are 5miles from home, don't persevere, park it up and get recovered. The fluctuations will get bigger and eventually you will blow virtually every bulb that is on, fry the headlight switch and the battery...

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