Tesla Air Suspension Pump Continuously Running
As first generation Tesla Model S cars are getting older now, owners are finding out new failure points of these cars as they reach 200k miles and more. Some problems will appear evident sooner as the car ages and other mechanical components will work well after vehicle reaches 100k miles and more.
I want to share a repair that may help other Tesla owners to fix smart air suspension. The problem I had with 2014 Model S that air suspension compressor pump stuck on and would not stop running. The first time I noticed this glitch that makes compressor running non stop, as soon I was able, I removed some plastic covers in the frunk and disconnected 12v battery and High Voltage loop plug. After a few hours I reconnected everything and car started working as usual. I thought it was a software glitch, the car completely reset by disconnecting the power and everything started working as usual.
Model S Air Suspension Compressor Failure
The second time (a couple months later) same thing happened, but I was not that lucky – disconnecting power did not work. After waiting an hour I reconnected battery, the compressor would still stay on and air suspension would try to level itself and drop lower and lower. It got so low to the ground that it was impossible to drive even mudguards would scrape. After pumping some air in to the system using schrader valve on the storage tank I heard air coming out from compressor. The pressure from over pumping had blown up a plastic filter on the compressor.
Tesla Model S Air Suspension Too Low To Drive
This happened in North County San Diego, about 45 miles away from home and car suspension being too low, I knew I would not clear even a smallest bump or even a lane marker. The only option was left is to find tow truck In Carlsbad and tow car back home to San Diego. Luckily my car was still driving and with some ramps and boards used for towing lowered cars they were able to safely load it on to the flatbed.
Replacing Air Ride Suspension Compressor
I went shopping for a used Tesla Model S air suspension compressor pump and found one at Autobahn Parts in El Cajon, CA. After getting a part I installed it and drove it for a whole week without any problems. But one week later, same malfunction happened again, the compressor pump would not shut off and stayed running, got hot, cracked plastic filter housing and started leaking air from the system. This time I new it was not a glitch and I had to find the problem before it burns up another pump.
After reading some more online I was pointed to either replace a valve block together with compressor pump or figure out what sensor or some other part doesn’t disable air pumping when system is full.
Tesla Model S Air Suspension Relay Failure Cause Compressor Burn Out
I found Tesla repair bulleting with air suspension repair instruction and it had emphasis on replacing K11 air suspension Relay with new one when replacing a compressor. My guess that 100 Amp air suspension relay DG85D-7021-76-1012-R wears out and gets stuck or over time internal contactors gets damaged from arcing and it fails to shut off power to the compressor.
After replacing air compressor again and installing new relay – smart air suspension started working as usual. It is recommended to fill the system with nitrogen up to around 200psi as regular compressed air may have impurities. I did not have nitrogen in my shop so I pumped up suspension storage tank with my compressor up 120psi and after reconnecting 12v car battery and high voltage battery loop I started the car.
After starting the vehicle air suspension compressor was pumping intermittent but after the pressure in the storage tank reached 200psi, everything was working normally and there was no excessive air pumping.
If you have older Model S and noticed prolonged air pumping for no reason you may want to quickly pull out K11 relay to prevent compressor from overheating. At first I did not know easier way to turn off the compressor quickly for I decided to disconnect 12v battery and High Voltage safety loop. This is not a professional advice, I am just sharing my way of repairing my personal car. I could not find much information online about my particular problem, when air suspension compressor stays stuck on pumping, so I thought this post could be helpful to someone.