I have read a few of the threads regarding the PSE pump in my model but I did not find one on how you go about finding a leak. Everything works in my S320 except the "Lumbar Seat Support system" in both the driver and passenger seats. Occasionally, I find the trunk handle has popped out as well. I took the back seat out and located the pump and left it off so I can hear it. I also took the seat backs off and can see the air bladders that I think should be pumped up with air. I looked all around the connections under the seats and up to the bladders and they all look fine. When I start the car the pump turn on (makes a sound) for about a minute then shuts off. I noticed it did the same thing a few times when I was at a stop light. I was thinking of taking the tubes off and pumping air through to find where the leak is but the tubes are attached very tight and I did not want to chance breaking anything. Does anyone know a method of troubleshooting to find where my problem is? Thanks in advance for any information.