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996 C4S ABS & PSM Light - Page 1 - 911/Carrera GT - PistonHeads UK

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Original source

6 captured repliesPartial discussion capture · Source accounts, not a confirmed diagnosis

THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCH996 C4S ABS & PSM Light - Page 1 - 911/Carrera GT - PistonHeads UK

Reported or suspected cause

mass air flow sensor

Reported cause

No successful repair reported for this finding.

1
Identified cause: 0
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 report identifying 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.

Reported cause
Just had similar issue, turned out to be the MAF.
Original post Read captured discussion
996 C4S ABS & PSM Light - Page 1 - 911/Carrera GT - PistonHeads UK

Frequently discussed work

Check tyre pressures first

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
Double check your tyre pressures first.
Original post Read captured discussion
996 C4S ABS & PSM Light - Page 1 - 911/Carrera GT - PistonHeads UK

Read full discussion summary

Leading evidence: 'mass air flow sensor' (1 discussions report identifying this cause; no attributable repair resolution). Across 1 matching discussions, the most frequently mentioned possible cause is 'mass air flow sensor' (1 discussions; 1 report identifying it and 0 suggest it). The most frequently discussed action is 'Check tyre pressures first' (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 · 6 captured posts examined · 1 partial discussions

Compare 3 other evidence results

Replace back

Performed · outcome unconfirmed

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
The ABS and PSM lights came on until I changed back to the normal air filter.
Original post Read captured discussion
996 C4S ABS & PSM Light - Page 1 - 911/Carrera GT - PistonHeads UK

Replace more switches than pressure sensors

Performed · outcome unconfirmed

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
Replaced more switches than pressure sensors
Original post Read captured discussion
996 C4S ABS & PSM Light - Page 1 - 911/Carrera GT - PistonHeads UK

Check tyre pressures first

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
Double check your tyre pressures first.
Original post Read captured discussion
996 C4S ABS & PSM Light - Page 1 - 911/Carrera GT - PistonHeads UK

Frequently discussed actions (3)

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

Check tyre pressures first

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
Double check your tyre pressures first.
Original post Read captured discussion
996 C4S ABS & PSM Light - Page 1 - 911/Carrera GT - PistonHeads UK

Replace back

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
The ABS and PSM lights came on until I changed back to the normal air filter.
Original post Read captured discussion
996 C4S ABS & PSM Light - Page 1 - 911/Carrera GT - PistonHeads UK

Replace more switches than pressure sensors

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
Replaced more switches than pressure sensors
Original post Read captured discussion
996 C4S ABS & PSM Light - Page 1 - 911/Carrera GT - PistonHeads UK

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.

mass air flow sensor

No successful repair reported for this finding.

1
Identified cause: 0
Suspected cause: 0
Reported fixes

Read evidence and context

Discussions that report identifying 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.

Reported cause
Just had similar issue, turned out to be the MAF.
Original post Read captured discussion
996 C4S ABS & PSM Light - Page 1 - 911/Carrera GT - PistonHeads UK

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.

PistonHeads: 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: 20261026T133652Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Hi all. My ABS and PSM lights are coming on with the first press of the brakes each day (resets when ignition is switched off). I'm a fair way from my Porsche dealer (70 miles) so wondered whether it was worth getting my local indie to deal with it. Anyone any ideas as to the most likely cause? Cheers

POST 2Original post

Braking. Wheel speed sensor would be possibility. Reading the error code would help.

POST 3Original post

Double check your tyre pressures first. It's odd that it's only when the brakes are pressed that the lights come on - normally if a wheel speed sensor is at fault the lights will come on as soon as the car sees that it's not getting a reading from one wheel when the other 3 are turning ok. I agree it would be useful to at least get an OBDII code reader on it - these can be bought for £20-30 from Euro Car Parts, also Amazon & Argos sell them, once you have one they're very useful for any car (from the late nineties on). Another common cause of those lights is the MAF failing, but that usually manifests itself in the lights coming on after caning it, not under braking.

POST 4Original post

Could be a faulty MAF. I changed to a K&N filter which my C4S didn't like. The ABS and PSM lights came on until I changed back to the normal air filter.

POST 5Original post

Just had similar issue, turned out to be the MAF.

POST 6Original post

My money's on Brake light switch. The system measures pressure and light switch input - if it sees one without the other then it will ping the lights on. Replaced more switches than pressure sensors

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