SAS Pump Running / Red SAS Icon

[ohmman]

In the 5+ years I've owned my P85, I've had a number of periods where my air compressor for the SAS runs indefinitely, then turns off and exhibits the red SAS icon (looks like an SUV with an up and down arrow). I have taken it in three times over the years, and they've found nothing. Generally, it has gone away by the time I get it to the Service Center. I'm out of warranty at this point, and I hate to take it in and have them tell me the same thing.

Has anyone else seen this behavior? I had something similar in my Model X, but it was a leak. They tested for leaks the other times I've brought it in, and didn't find any. Once it goes away, it seems to stay away for months or a year. Very odd.

I'm able to raise and lower the vehicle from the lowest to highest setting. If I'm guessing at anything, it appears to be more based on adapting to driving dynamics, because it'll stabilize if I'm parked but as soon as I start driving, will kick back up again.

 

[jerry33]

That sounds as if the sensor has an issue.

 

[David.85D]

Sounds like you have a small intermittent leak in the air system.

(Leaks) used to happen on my air suspension X5. You will burn out the pump if you don’t get it fixed. They aren’t designed to run all the time.

If you are the diy type, take the frunk tub out and spray some soapy water on all the air tubes and connectors to look for leaks.

Since it comes and goes, maybe it’s only pulling on a loose connector at high or low settings? I’d check everything at low, then high, move the wheels from left to right, etc,

Have you looked to see if one corner is lower after it sits awhile? Might be a clue

 

[David.85D]

BTW, I also had one height sensor fail on my X5. That caused it to raise up until it reached the limit of travel and didn’t come down until I removed an air fitting to release the pressure. Luckily it was the rear. Car looked pretty cool like that

(don’t let anyone tell you the Tesla’s are unusual or fail too often... with a few exceptions, they are using the same globally sourced parts as everyone else )

 

[ohmman]

Tesla has had the car for a few days and have been a little confused by the behavior. They plan to replace the compressor and valve tomorrow.

My loaner S is a tight vehicle. I'd forgotten how far along they've come with quality control on the cars. Mine rattles a bit going down my gravel road every day; this one is silent and smooth. No worries, though.. still love my S.

 

[scottm]

I think there's a schrader valve on the air tank that sits up high under the cowl. You might be able to access just by popping off the cowl plastic piece under the hood.

Put a gauge on it. Watch the pressure of the tank while this is going on to see if it comes up to pressure. Then pull the air compressor fuse to stop the pump and see if pressure starts dropping. If the pressure doesn't drop, there's a bad cut-off limiter sensor on the tank. If the pressure drops you've got leak.

Triangulate to find the corner having the leak by pulling its line from the manifold/splitter of the air distribution controller, and swapping it out with a small vessel (that can hold a pressure) with plastic line. If the running pump stops for a given "corner" you've found what to chase down next to that airbag.

If you chase it down right up to an airbag, disconnect the bag from car, and pump it manually to a pressure and see if it holds or is the leaky culprit.

 

[365gtb4]

I wonder how the system deals with water buildup? Air compressors have manual and automatic drain valves to remove the water. Is their a drain on the reservoir tank?

 

[scottm]

I wonder how the system deals with water buildup? Air compressors have manual and automatic drain valves to remove the water. Is their a drain on the reservoir tank?

Good point.

 

[ohmman]

Good question on the water buildup. There must be an automatic drain, since it's not a service concern.

I got the car back today, here is the service note. They were kind enough to do it as goodwill, since I'd taken it in during warranty for the issue.

Concern: Air suspension icon lights after pump runs indefinitely. Have brought the car in twice before for this issue without finding the issue.

Confirmed customer concern. During inspection found internal fault in air suspension compressor to cause k11 relay to blow. Replaced compressor, blown relay, and performed calibration procedure. Verified air suspension now operates as designed.

Correction: General Diagnosis

Correction: Compressor - Air Suspension - 1st Generation (Remove & Replace)

Parts Replaced or Added
Part Quantity

AIR SUSP COMPRESSOR(6006403-00-A)

Correction: Relay in Fuse Box - Any (Remove & Replace)

Parts Replaced or Added

1.0

Part Quantity

RELAY,SPST,NO,12V,100A,PLUG-IN(1009577-00-A) 1.0

 

[ElectricTravel]

I wonder how the system deals with water buildup? Air compressors have manual and automatic drain valves to remove the water. Is their a drain on the reservoir tank?

The air suspension system is filled with nitrogen at the factory, so there should be minimal moisture in the system as long as there are no leaks. In normal operation, the system is just moving air/nitrogen back and forth between the tank and the air springs as needed.

If there's a leak and the system needs to introduce ambient air, there's an air dryer inline with the air intake.

The system can exhaust compressed air back to the atmosphere through the same air dryer and intake line; doing so allows it to "regenerate" the air dryer by forcing out moisture. I suspect this is what's happening when you hear the compressor running for several minutes and blasting out air occasionally, sounding like a truck with air brakes.

 

[bmah]

Interestingly I had this symptom a few days ago...it went away when I did a power-off of the car and turned it back on. (I know that's not a great solution.) This has happened maybe twice in the past 4.5 years. I wonder if I should get this looked at...

Bruce.