Strange Braking Issue

tchavei

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I'd need to check. That's a job for the morning, thanks.

I've never seen the green on the power meter at all under any circumstance.

I'd need to look up how to enable overrun recuperation. Is that via the PCM?
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DynamoCappo

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Ah, yes!

I've put that on briefly before but it was a 1000 miles ago and I only really noticed the braking reacting slightly differently as per an EV type regen. There was no green light back then but I'll check again tomorrow with the additional miles on it.
 

whitex

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I'd need to look up how to enable overrun recuperation. Is that via the PCM?
In PCM in drive mode settings, or a dedicated button on the steering wheel. It’s not very strong but enough to see it on the power meter and independent from brake pedal. It would tell you if your car can regen at all.
 

DynamoCappo

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In PCM in drive mode settings, or a dedicated button on the steering wheel. It’s not very strong but enough to see it on the power meter and independent from brake pedal. It would tell you if your car can regen at all.
So the answer to that, this morning, was no then.

I used the button once or twice to see if I liked the feel of it when I first got the car and preferred it without so haven't used it since.

Engaged it this morning and there was no green bar at all. Switched it off and on again at a couple of points over the journey and it made no difference.

The breaks are definitely still spongy at that 5mph mark. It's more noticable when you're, initially, slow moving around 10mph or so and applying pressure with that last 5mph now needing an extra push, rather than a linear pressing, of the pedal to get to a complete stop.
 

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So the answer to that, this morning, was no then.

I used the button once or twice to see if I liked the feel of it when I first got the car and preferred it without so haven't used it since.

Engaged it this morning and there was no green bar at all. Switched it off and on again at a couple of points over the journey and it made no difference.
Was the car feel any different. If not, you might have a broken regen/recuperation. This might explain why it doesn't kick in when you hit the brakes too.
 


DynamoCappo

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Was the car feel any different. If not, you might have a broken regen/recuperation. This might explain why it doesn't kick in when you hit the brakes too.
You can feel it different, yeah. Lifting your foot off the accelarator with the mode on does feel like it's slowing the car down more so than normal coasting would.

I think this issue is separate to what might be an actual problem with the regen not having kicked in yet.

This has just started to feel different since yesterday morning. I'm certain I would have noticed it in everyday driving before now if it was a thing the car was meant to do.

I drive the same route pretty much most days and there's a difference to that specific point of breaking.
 
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W1NGE

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You can feel it different, yeah. Lifting your foot off the accelarator with the mode on does feel like it's slowing the car down more so than normal coasting would.

I think this issue is separate to what might be an actual problem with the regen not having kicked in yet.

This has just started to feel different since yesterday morning. I'm certain I would have noticed it in everyday driving before now if it was a thing the car was meant to do.

I drive the same route pretty much most days and there's a difference to that specific point of breaking.
What is the experience like with Drive Mode - Sport / Sport Plus (regen will always be active)?

Bear in mind, no regen at crawling speeds, you have PCCB by the looks and so behaviour may be quite different anyway, recup should kick in around 700+ miles or so, not available first thing when cold - takes about a mile.

Recuperation will be as clear as day when the Power meter is displayed - any recuperation mode and when braking - and the above conditions met. If not then potentially there is an issue.

Recuperation retardation is definitely noticeable in any drive mode when available. When coasting the Power Meter won't register anything unless you have ACC or CC active.
 

DynamoCappo

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What is the experience like with Drive Mode - Sport / Sport Plus (regen will always be active)?

Bear in mind, no regen at crawling speeds, you have PCCB by the looks and so behaviour may be quite different anyway, recup should kick in around 700+ miles or so, not available first thing when cold - takes about a mile.

Recuperation will be as clear as day when the Power meter is displayed - any recuperation mode and when braking - and the above conditions met. If not then potentially there is an issue.

Recuperation retardation is definitely noticeable in any drive mode when available. When coasting the Power Meter won't register anything unless you have ACC or CC active.
On the way to work this morning, there was a warning light appeared on the dash saying "PSM Failure. Visit Workshop. Adapted driving permitted"

When that came up, I googled it and found this thread from last week.

https://www.taycanforum.com/forum/threads/braking-issue-psm-failure-with-video.15783/

That's the exact problem I'm having. Going by the replies it's either going to require the brakes being bled for air or a new module of sorts.

Called them at 9am this morning to see what to do. Was told someone in service would phone me back. Hopefully they call before much later on today as if I have to take it to the dealership tonight, I'm going to need a courtesy car.
 

DynamoCappo

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Update on all of this then...

Back in May, they bled the brakes and it improve for a few weeks and steadily started to become an issue again.

I really noticed it at low speeds pulling into parking spaces and the pedal would engage initially and then travel for ages before you got anything from it to bring you to a stop.

When the PCM / Battery recall came in before Christmas, I had it booked in for January and they looked at the brakes again the other day.

They've bled the system again AND it seems that Porsche have also issued a new directive for works to be carried out as part of this operation on top of them being bled.

I've to keep an eye on it again and if it regresses like it did before, at that point they'll fit the new module.

Hopefully this solves it, but at least I know what the next steps are if required.
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