Deikoo

Hey, same problem here: I have a 2004 Cayenne, and pretty much I have the same problem, the error message that says "...amplifier no available". the navigation works, but no audio at all. I disconnected the CD changer, and nothing changed, but the message that only says that the amp doesn't work. Now, it started with intermitten frequency, a day it was working, the other it wasn't. I turned off the engine and restarted it and it was working. Loud noise and stopped working, not working at all. Now it hasn't worked for a month, and yesterday once gotten to destination, I stopped the engine, removed the key, and thought to start the radio and ...bang, it worked! I repeted the experiment today after the 16 miles trip to the office and it worked again. So what the F... is going on? it's not the amp, it's not the optical cable in my opinion, it's not the fuse....what the heck is it?

I thought it could be a ground problem. Not at the battery though, I had the battery replaced a week ago, and thus (I want to hope) the job was done correctly and all nuts and bolts were tightened. so.... i checked the ground bolt in the rear of the vehicle, left and right in the trunk inside where you have those emplty spaces. they seem ok to me, so.... WHY WHY WHY all of the sudden? what is the cause? what is it?

I should check the AMP in the rear (right side of the luggage). My experience says that the hose for rear window washer is broke (in the sealing above the amp) and therefor it comes washer fluid on the amp.

it happened again today. :(

do i need some special tools to check the vacuum pump and hoses?

Yes, you do. You need a special tester that can build up the vacuum to -400 to -600mbar in the brakebooster and then let it stay there. After a while you will read out the values and see if it is the same vacuum.

To check if the vacuum pump is OK you will need a Porsche system test II. It will do the adaptations och se if it is OK.

Take the car to a Porsche workshop =)

Why so complicated?

If you cant change the gearstick. Some signal is missing to the control unit. You have ABS and PSM fault aswell. You need signal from the brake switch to release the gearstick. If you are missing signal from that switch you cant move it. The ABS and PSM control unit needs that signal aswell, otherwise this alerts will come up.

Simple test, Do the brakelights go on when you press the brake pedal?

It happened again.

Got the brake code:

P1431

Brake Booster System - Signal Implausible

(The brake system is working just fine at the same time)

Got another code in electrical system simultaneously:

Fault code 0907

Load management operation on vehicle electrical system/

DME control module

Possible causes of fault

♦ 'no display' Loads are/were switched off temporarily. The load

management operation was enabled because of undervoltage.

Also noticed that this usually happens when the car has a few back to back short trips in one day.

All these above makes me wonder if I need to get a new battery for my cayenne (80k on the clock)...

Possible fault cause (P1431)

♦ Leaks in brake booster system

♦ Vacuum pump worn out or mechanically faulty

♦ DME control module faulty

Does anyone have a copy of PCM install instructions for latest version?

i just received 08.2009 updates for my NAV.

came with 3 discs:

1. Map DVD

2. PCM 2.1 Multimedia Update CD Cayenne

3. PCM 2.1 Multimedia Update CD Navigation

thanks

matt

With the car running, i believe you remove your old Nav DVD, then Insert Disc 2 in the Head unit till its done, then Disc 3 in the Head unit until done, then place the Nav DVD in the DVD drive.

Remember that DONT TURN OF THE POWER when the PCM is updating. Doing so will cause software error and you need to replace the PCM.

Thanks,

You know, I have been kind of assuming the battery is fine as it was replaced less than a year ago, but now I am remembering that the shop that changed it told me they had found that the one they pulled out "was the wrong battery". Perhaps they were mistaken, and this new battery is causing problems.

In terms of trips, we do use it frequently for shorter distances - let's say 10 KM per trip daily - but not little trips to the corner and back. But having said that, they are mixed with semi-frequent longer trips of 300-400 KM. I am going to look into the battery and will post back the results.

Is it also possible that the alternator is failing to charge it properly? or is that more of an item that will either work or fail - not degrade?

When you are driving short distances, the generator cant refill the power that are needed when the car starts. The starter takes a lot of power. Thats why I asked that question. If you are going at longer trips some times, then the battery will load up.

BUT... If the battery goes almost empty a couple of times, it will be weaker.

The generator are often in full function or broken in these cars. Nothing in between. Ofcourse some cars will have a half broken generator but I havent seen it yet. (worked with porsches for more than 3 years)

If you can, try to put a charger over night and see if the problem are gone next time you start the car. If its gone, then its defenetly the battery.

I have looked at maintanance checklists in this forum but still dont understand as my car first said Service at about 3000 miles (cannot rememebr now) and now it says service and there is 12k miles on the clock. it is not a problem warning as it started saying service in 1k miles, 0.5k miles etc etc. it also doesnt corresponde to any time intervals (manufactured in July, bought in August 2008). Any thoughts?

nothiing in service boook about what needs to be done.

Check in your maintence book. I dont know how it is in the US but in europe its 30.000 Kilometers or every two years. Its the number you are first to reach that you should go after.

If you read the book you should be able to see whats right for your car.

yes engine was on while i was filling Gas up

it seems i have to take it to dealer to remove the warning

You triggered an "EVAP system massive leak" CEL by not turning the engine off while refilling. These cars have a closed loop vapor control system on the fuel tank, running the car with out the gas cap makes it look like a vacuum leak. It should eventually clear itself after several running cycles if you do not repeat the mistake..............

Im not so sure that it dissaperas after a couple of driving cycles. IF the car has "EVAP system massive leak" the car has to light the warning up beacuse the ristriction of exhaust laws.

Not sure about the US cars but they have more laws about that so I think it is worse with US cars.

That was a low level of octane... here in sweden we have from 95 and up to 99 octane :D

Hi,

Just disconnect the connecter from the gray box.

Just be careful, the valves can get stuck if you have it disconected all time. They are not for free :)

If it is a model of 2008 the problem looks like a bad high pressure fuel pump.

Did you have the engine on when you filled up gas? I suppose so...

The gas system in the car needs to be closed (gas cap closed, etc) otherwise it takes in air and the control units gets faulty values.

Go to a porsche dealer and have the warning removed.

Do you have roof lid on the car ?

This faults are the most common when you have lack of power in the battery.

The questions for you is, do you only drive short distances? Do you often let your car rest in a week or two?

If you have answered yes of one of these two, I should replace the battery :)

One more thing, do you have two batterys in your car? The dealer mabye changed one of those ?

Its probabley the Pressure sensor that is the problem. Either broken or contact faulty.

This fault can be displayed when the battery is bad. BUT, only if it comes up when you start the car. It can be the 4 wheel drive motor aswell. Check the battery first.

In the Cayenne, you have a MOST line that goes from the PCM (head unit) to navigation unit, BOSE amp, telephone, tv and other external components that are connected to the PCM.

When this fault (error) comes up, the MOST line is broken in some way. It can be the connections, yes. But most likely its one of the external components that are broken. When a externa component is broken, the MOST line is cut. If you want to test the components you need to have a MOST dummy that you plug in instead of, lets say the amplifier. If no error comes up, the amplifier is faulty. If it still comes up, try one of the other external components.

If the amplifier is broken, check if it has come water on it. If it is so, then you should check the rear washer system for leakage inside the car.

Sorry for my grammar but im from Sweden ;)