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Cayenne S - start/stop fail, engine light on - Page 1 - Porsche General - PistonHeads UK

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

THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCHCayenne S - start/stop fail, engine light on - Page 1 - Porsche General - PistonHeads UK

Leading reported evidence

Replace assist also fails now and

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
The ACC and lane change assist also fails now and again.
Original post Read captured discussion
Cayenne S - start/stop fail, engine light on - Page 1 - Porsche General - PistonHeads UK

Read full discussion summary

Leading evidence: 'Replace assist also fails now and' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Replace assist also fails now and' (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 · 4 captured posts examined · 1 partial discussions

Compare 2 other evidence results

Run continuously

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
A possible cause I have seen previously is related to your symptoms; the DME CU needs permanent comms with the fan controllers - if that link has failed the fans will run continuously to protect the drivetrain from overheat conditions; so it it may be a simple wire break rather than a component failure.
Original post Read captured discussion
Cayenne S - start/stop fail, engine light on - Page 1 - Porsche General - PistonHeads UK

Run miles) has started playing up

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
My cayenne s (69 plate, 25,000 town running miles) has started playing up with the start/stop failing, engine light now on (not flashing!).
Original post Read captured discussion
Cayenne S - start/stop fail, engine light on - Page 1 - Porsche General - 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.

Replace assist also fails now and

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
The ACC and lane change assist also fails now and again.
Original post Read captured discussion
Cayenne S - start/stop fail, engine light on - Page 1 - Porsche General - PistonHeads UK

Run continuously

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
A possible cause I have seen previously is related to your symptoms; the DME CU needs permanent comms with the fan controllers - if that link has failed the fans will run continuously to protect the drivetrain from overheat conditions; so it it may be a simple wire break rather than a component failure.
Original post Read captured discussion
Cayenne S - start/stop fail, engine light on - Page 1 - Porsche General - PistonHeads UK

Run miles) has started playing up

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
My cayenne s (69 plate, 25,000 town running miles) has started playing up with the start/stop failing, engine light now on (not flashing!).
Original post Read captured discussion
Cayenne S - start/stop fail, engine light on - Page 1 - Porsche General - 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.

4 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: 20261026T152433Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

My cayenne s (69 plate, 25,000 town running miles) has started playing up with the start/stop failing, engine light now on (not flashing!). The ACC and lane change assist also fails now and again. This has been happening for a week and the engine fan goes crazy when I switch the car off. Any one have this problem? Is it time for a dealer visit? Thanks

POST 2Original post

Might be worth getting a code reader on it (porsche specific ones availiable for just over £100 from ebay - icarsoft is the one i have) It will cost you a few quid just to get the garage to do that. Once you have the codes a quick google will give you an idea of what might be wrong. No personal experience here, but I heard stop start can go crazy if the battery is on it's way out.

POST 3 / ORIGINAL POSTEROriginal post

Thx! I’ve looked at a scanner and have decided I’m out of my depth so have booked the car in for a diagnostic. Here’s hoping for an easy fix. I’ll post the update here in case useful to others.

POST 4Original post

Hope you get it sorted; the network stress has backed down a bit recently so booking in should be quicker! A possible cause I have seen previously is related to your symptoms; the DME CU needs permanent comms with the fan controllers - if that link has failed the fans will run continuously to protect the drivetrain from overheat conditions; so it it may be a simple wire break rather than a component failure. The diagnosis system will have a code stored in the above case. Keep this thread updated.

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