wurlycorner

Hi
Recently joined member, have gratefully used previous posts on the forum to help solve some issues before - thanks all - but can't find anything that matches current symptoms?

This is on a UK 2012 Cayenne diesel.
Previously there were 'key not recognised' faults continually going off while the car was being driven, which I traced to faulty door close buttons on the drivers side (front and rear) stuck on and I de-pinned the relevant wire from the plugs/taped it back to remove that fault.
It's then been fine for several weeks; but this week a new key related fault has arisen
I should add, this is on a friends car, not mine - so unfortunately I haven't yet had a chance to pull the stored codes: I only have a description of the symptoms and photo of the error messages on the dash, for now. Just trying to get ahead of the game from when I do see the car (maybe tomorrow).

Symptom is: Car unlocks ok, but sometimes won't start (no crank).
Dashboard displays "key not recognised" and "Panel: turn left, remove, Insert Ign. key".
The car has the dummy key fitted in the barrel and the remote key battery has been replaced within the last couple of months (so should be ok?).
I have asked if they've swapped to their spare key to see if the fault doesn't occur with that, but don't think they've had a chance yet (both remote keys work ok - confirmed this during the previous 'key not recognised' faults!).

I assume that fault message is asking us to remove the dummy key and put the proper key in the ignition barrel - but I don't know why that should really make a difference and whether it means we can then go back to using the dummy key, or not?
I'm hoping it is just a flat key battery - but it hasn't given a fault code on the screen, saying that.

Any thoughts from anyone, please?

nb: I use a ThinkCar ThinkDiag+ (with the manufacturer specific diagnostic software) for diagnostics.
After the last round of fault fixes on it (there had been quite a few different faults that I fixed, before the key fault!) the following codes were still 'active':
84040E - Roof Control Unit, Interior Lighting Faulty
C13212 - Communication With Alarm Siren (Rear 2)
C12085 - Check PSM Control Unit Fault Memory Content
0007B1 - Seat Depth Adjustment Button Up (Mechanical Fault)
008320 - Communication With Sun Sensor (LIN Bus Vehicle)
000843 - Central Locking Closing Unit, Implausible Signal

The following were stored 'inactive'
881202 - Key Battery Flat
880F01 - Closing Button FR Pressed For Too Long
881101 - Closing Button RR Pressed For Too Long

881101 and 880F01 are left from before I de-pinned the button (I didn't clear the fault codes)
000843 I know is a faulty right left central locking unit (I will be changing the lock shortly). I haven't had a chance to investigate the others yet, but they don't cause error messages on the dash/any day-day issues.

Thanks in advance!

dan212

Is there any possibility that this is location specific? I live in NYC and within 20-60 feet of my girlfriend's building, I get this error. Turns out there is someone in a nearby brownstone with a lot of very high powered government level communications equipment. Happens in a few other places. Nothing wrong in the car. Signal interference.

wurlycorner

Interesting - yep, I can understand how that could be an issue (though rare).
I'll talk to them and find out where it's happened/if only at one particular location.

In the meantime, does anyone know if there's a particular way of testing each of the antenna's for the system?