Hi, on my X350 MY 2003 the air suspension was totally down. After lifting one damper up (direct electrical connection to +12V source and reconnecting to original wiring harness), the whole system went up again and all 4 dampers are up. Only the one, which I have manually lifted up is a bid deeper than the others. Additionally the system is extremely stiff and not comfortable. On the dashboard the yellow and red leds are blinking.
What could I do or how to proceed further? Does anybody know this fault? Before it had a suspension fault message in the display. After erasing the fault, the ASU module is now fine, but still red and yellow blinking lights and very stiff / uncomfortable suspension.

 

If you have deleted the faults, they will reoccur if the condition that gave rise to them is still there. In order to give advice, please tell us what fault codes you have by reading them with the same apparatus you used to delete them.

If there is any fault in the system, the ASM defaults the shocks to 'Hard'. That's why you have a stiff and uncomfortable suspension.

 

Hi, I could solve the issue:

First step was to switch off 12V for a night.
The fault (upto that point I did not know it was a fault) config b got erased.
After this the fault suspension fault came back again. This is always the case, because of a new required configuration of the ASM (air suspension module).
​​​​​​This can be done by switching the suspension to customer mode (before it was still in transportation mode and the reason for the stiffness.
After this I levelled the system and measured the ride height. Voila, issue solved!

Hopefully this helps other people.

 

The Jag Repair website is down today to get a full schematic but I have this half of the switch

Missing pin 3 and 4

The pin 1 is provided a ground.in normal operation but if power goes down that direction it would affect the SLCM

by adding power on the bck of the brake light relay you would only block the relay pulling coil from closing and should not be an are of interest.

If anyone has the 2000 wiring guide other then the Jag Repair website I can get the complete 4 pin switch and the items affected

The way the SLCM pin ST2 - 1 works is it is already putting a sensing or feeling voltage out seeking a ground through the brake switch pin 1 to 2

When the ground is found the sensing voltage goes to zero triggering the SLCM to do it's thing on the brake light aspect.

So in my opinion the SLCM has not been effected.

The other systems to look at are the antiskid , cruise control , and transmission ECU that I can think of without the complete schematic