Porsche cayyen ignition problem

[FaFa]

Hi all, I have a cayenne Turbo and recently has on-off ignition problem. It would not ignite, though lights are on and battery is fine. It is a system issue it appears, as every time the battery is disconnected or computer is disconnected, it would ignite like normal. But then the next day may not. I need help

[Mighty Mike]

Probably one of the ECUs is not talking to another one causing the car to be immobilized and battery disconnect offers it one reset. I've see this in a another European SUV too, a locking mechanism in the steering column fails so the ECU thinks car is not safe to operate with a locked steering so does not send the signal controlling ignition. 

[Gaurav]

Get the scanning done to find out what's actually troubling and change that sensor, module or part. German cars are good in a way to pinpoint in the right direction, so stay away from a rookie mechanic who will sell you 3000 dhs story for changing 300 dhs sensor.

[Barry]

So the ignition is coming on but the starter motor isn't turning?

[FaFa]

I already tried two good places, and none has worked, let alone 4000 aed paid. People say take it to Al Nabboda. but is very costly. 

2 minutes ago, Barry said:

So the ignition is coming on but the starter motor isn't turning?

The lights come on, but the engine wouldnt start.

[Gaurav]

OMG, that sounds serious than I thought. Please contact below guy who I used to take my Cayenne Turbo, gem of a guy and Porsche Specialist. Give my Grey Cayenne and Carnity reference, he will help you as much as he can. 

Abu Hassan - 050 4559177

[Barry]

9 minutes ago, FaFa said:

I already tried two good places, and none has worked, let alone 4000 aed paid. People say take it to Al Nabboda. but is very costly. 

The lights come on, but the engine wouldnt start.

Ignition, no crank faults are generally simple and any decent mechanic should be able to solve it.

When you turn the ignition on, a notice comes up on the dash board to tell you to press the brake pedal before you start, does this warning go away 100% of the time when you press the pedal?

[FaFa]

15 minutes ago, Barry said:

Ignition, no crank faults are generally simple and any decent mechanic should be able to solve it.

When you turn the ignition on, a notice comes up on the dash board to tell you to press the brake pedal before you start, does this warning go away 100% of the time when you press the pedal?

Yes. It does. In case of car not starting this message is not shown, whether brake is pressed or not.

 

1 hour ago, Mighty Mike said:

Probably one of the ECUs is not talking to another one causing the car to be immobilized and battery disconnect offers it one reset. I've see this in a another European SUV too, a locking mechanism in the steering column fails so the ECU thinks car is not safe to operate with a locked steering so does not send the signal controlling ignition. 

the problem is it is unexpected when it does not work. Sometimes it works for few days, but recently is getting worse and it may start even after one hour . only immediately after computer re-start it works.

[Barry]

Could be a problem with the dash clocks. Really, you need it plugged into a computer to read voltages and live data to see what's going on during the start procedure.

[treks]

8 hours ago, FaFa said:

Hi all, I have a cayenne Turbo and recently has on-off ignition problem. It would not ignite, though lights are on and battery is fine. It is a system issue it appears, as every time the battery is disconnected or computer is disconnected, it would ignite like normal. But then the next day may not. I need help

Fault codes? It's like Barry says- a lot of things happen during a start-up, and all of these things that need to happen are interconnected. If one fails to happen, the whole procedure is aborted, so without fault codes we are just guessing. 

What makes it more difficult is the fact that this is an intermittent issue, so even if you have the fault codes,  finding the actual fault or poor connection can be as easy as wiggling the wires, replacing the brake switch or starter relay-  or pulling out large sections of the wiring to check each connector and connection individually.  

Edited April 17, 2018 by treks