OBC Message "Emergency Transmission Run"

[MWS]

My '09 C4S with PDK has 15,000 miles. I had not driven the car for three days. The weather for central Texas has been very cold during this three day period - into upper 20's F at night and 40's-50's F during the day. The car started easily and I let it idle for a minute or two while I entered a destination into the navigation system. When I shifted from Park into Reverse nothing happened. The engine would rev but the transmission would not engage. I thought that maybe I was in neutral so I shifted into Drive - same thing happened; the engine would rev but the transmission would not engage. I shifted into Reverse, then Park, then Reverse, then Drive several times and the transmission still would not engage. The OBC (On Board Computer) displayed "Emergency Transmission Run" and there was a red exclamation mark illuminated on the tachometer. I shut down the engine then restarted it and the "Emergency Transmission Run" message and the red exclamation mark were both gone and the transmission would now function properly. I drove about 60 miles without any further problems.

Has anyone else had this problem?

Any comments?

[RFM]

Get the fault codes read, could be just a communication problem. MY09 cars are still under warranty, let an OPC solve this problem.

[MWS]

This morning it happened again. I went out started the engine, shifted into reverse and the transmission would not engage. Shifting into Drive and Park etc made no difference. The same warning message was displayed. the problem resolved by shutting down the engine and then restarting it. This makes two failures in 48 hours.

I called the dealership in Austin and was told to bring the car in. I'm driving a loaner Cayenne now. (I much prefer my C4S!)

I will post the outcome of this problem when I get my C4S back.

[RFM]

Thanks, feed backs are highly appreciated.

[MWS]

The dealership's resolution to this problem was to "reload the software" for the PDK transmission.

My guess is that the problem has not been resolved and it is only a matter of time and it will happen again.

The service writer did admit to me that this is a known problem to Porsche but it is a new problem to my local dealership.

[RFM]

A software update with the latest version could be the solution, this intervention is not unusual, wait and see.

[Gio]

I have a 2009 Cayman S with the PDK unit. The car has 9k miles on it and is garaged kept. I use this car on the weekends to go from house to restaurant or no more that 15 miles one way. I have a second car I use for work, etc. I "baby" this car and have not gone past 75 mph for anything. Launched it once with the sales guy when the time came for a Demo on the Launch Control feature.

Sunday afternoon I took it out for a short ride. Only a few blocks from the house the car began to experience problems. The RPMs would go up and up with the car not going above 20 mph. I watched the gears shifting up through to the 4th gear. The RPMs would not go down at all even when it would shift up in gears unless I let off on the accelerator.

Finally, I would let up on the accelerator and the car would stay in 4th gear as it slowed down (without me applying the brakes). I would then attempt to accelerate with only the RPMs going up and without the car picking up any new momentum forward. Eventually the PDK would kick in and shift into gear and lurch forward. This happened multiple times while I tried to get the vehicle back home into the garage. I tried to shift the car back into park and see if this fixed the problem. It did not. The "Check Engine at workshop" light came on throughout all of this.

I brought the vehicle to the dealership and they are having discussions with Porsche about a fix. They are talking about possibly reloading software or upgrading it. However, indications on the technician findings are leaning toward replacing the entire PDK unit. They are having further discussions today with Porsche whether or not to go ahead and replace the PDK unit altogether.

I have found a few items out on discussion boards on this very subject with the PDK unit. Most of these cars are from 2009 or 2010. The fix is to replace the unit and ship the old to Porsche for forensic analysis. However, I am concerned about the future. Although Porsche is willing to provide a fix to address my problem by replacing the PDK with a new one, I feel it is a temporary band-aid. What guarantees do I have the new unit will not experience the same problem and worse it occurs after my warranty is expired. This to me is unacceptable and reason for concern.

Has anyone experienced this issue and how many more of us out there are having similar problems? What is Porsche going to do to stop this similar and on-going issues with their PDKs? Frankly, nothing short of a re-design or revised version of the old PDK is good enough in my opinion. Your thoughts and input, please?

[JFP in PA]

Automated sequential manual gearboxes, such as the PDK, are pretty complicated. There are multiple sensors, actuators, and of course, lots of software to make this all work smoothly and without reducing everything to rubble. One of the major downsides to all this complicated technology is that there are a lot of potential failure points, any of which can stop the process cold. Added to this is the fact that these gearboxes are a world unto themselves when it comes to special diagnostic electronics, fixtures, and tooling required to disassemble or repair them in the field; and then you have to train personnel to do the diagnostics and repairs. The end result is that the dealers are often ill prepared to deal with issues, or spend a vast amount of time trying to figure out why the gearbox does or does not do some particular task. End result is that they try a quick software re-flash, and then pull the unit if that does not work. You also have to remember that dealers do not get reimbursed at their normal retail hourly rates on warranty work, so they don't want one of these to turn into the proverbial "hanger queen" on them either.

Porsche is not alone in this; I recently stopped a local Nissan dealer to pick up some parts, and they were trying to figure out why a brand new GT-R's version of the PDK would not shift when you hit the paddles manually. After two days of diagnostics and software re-treads went nowhere, they opted to pull & replace the gearbox, resulting in the car's owner having a fit and demanding a diminished value refund because the car would no longer be "numbers matching".

I know this doesn't do much to allay your concerns, but unfortunately it is the reality of this technology. As the owner of an independent shop, I am very concerned about how we are going to deal with these units when the cars are out of warranty; the potential costs for my shop to "be ready" are significant, particularly when it does not currently appear that the OEM's are going to do anything to share the technology, or even make parts available to the aftermarket. Down the road, a simple "pull it and replace it" approach is not going to be viable; I saw the replacement gearbox for that GT-R, the dealer's cost (what they would normally pay for it) was over $18,000………..

[Gio]

JFP - thanks for the feedback.

My worries look to be valid then. The Porsche was able to re-create the problem on my car. They found the gearbox fluid low and so they replenished it. Also, they upgraded the software for the PDK.

Now they are telling me that they test drove it 4 separate times in one day and checked the fluids onces it cooled. Everything is back to normal.

They are just waiting to compare their computer diagnostics with a Porsche location in Atlanta to to see if replacing the PDK is warranted or if they will return the car back to me.

I informed Porsche that my own research online found similar separate incidents with the dealership performing their due diligence with the diagnostics and software upgrades only to eventually default to replacing the PDK unit. They acknowledged the statement and that was that.

Hopefully I will get my car back in the morning. However, it looks like I will continue to be a guinea pig moving forward. By the way they did suggest I get an extended warranty to alleviate my concern about future issues with the PDK. I guess it is much cheaper than the alternative.

[JFP in PA]

Right now, there are not a lot of options available. While I am anything but a fan of aftermarket warranty products, if the dealer’s program is a sound one, it may be your best option.