If your S Class has suddenly dropped itself on to all 4 wheels where the inner wheel arches are almost resting on the tyres and your dashboard is displaying a warning related to the Air Matic system and asking you to visit the workshop, then the most likely cause of this problem is the air matic pump failure.
The Air Matic system is located on the driver's side ( UK RHD Models ) under the wheel arch mud guard. The mud guard is held in place by quite a few plastic nuts as shown in the pic. After disconecting the negative terminal on your cars battery, you can start removing the mud guard.
Removing the mud guard reveals the Air Matic Pump which is held in place by 3 nuts which go on to spikes protruding downwards. There is a single nylon pipe which connects to the air matic pump, a single black hose and two electrical plug connections which need to be disconnected to remove the air matic pump.
We had problems removing one of the electric plug connectors as it would not move at all from its position so we decided to cut the wires as shown in the pic. Once the pump had been taken off, it took the use of a pair of pliers and a straight head screw driver to get the plug to come off.
Once the new Air Matic pump had been sourced from Mercedes Dealership, we realized that the design for the new pump was slightly modified. The hose connection for a rubber pipe had been moved from its original position to the other end. We decided to improvise and use a slighly longer hose to get the job done making sure the new pipe had no kinks which would hinder the flow of air to the pump.
Brake Pad replacement is very similar for many different models and the main principle is almost exact so this guide is intended to give an illustration into the process of renewing your cars brake pads easily and efficiently.
The yellow brake light on your dashborad is flickering and you may also be hearing some grinding noises whilst driving slowly. YUP you guessed it, it's time to change the brake pads.
The first step is to give the brake pads a quick inspection. If you have alloy wheels with decent sized holes in them as shown in the pic, it will be possible to see the thickness of the brake pads without having to remove the alloy wheel.
After placing the jack under the car and rasing it enough so that the wheel is just about still resting on the ground, the wheel bolts should be loosened. It's always good practice to also place some additional axle stands in other secure places underneath the vehicle.
Once the alloy wheel is off, it becomes clear that the pads were extremely low as shown from 2 different angles.
Pop the bonnet open and remove the brake fluid reservoir cap. This is to release any pressure once the brake calliper hydraulic unit is moved back to accomodate the new brake pads.
The brake calliper is held in place by 2 x 40T star key bolts. Usually the lower bolt can be opened which allows the brake calliper to swing upwards allowing the brake pads to be replaced but in most cases, both the star bolts may have to be opened if the calliper does not seem to move freely.
Once the 2 star bolts are off, the calliper may need some hammering to assist taking it off. Calliper should be hammerd from the bottom and inside and it should slowly move upwards and outwards eventually revealing the brake pads.
Once the old brake pads have been removed, the hydraulic unit on the brake calliper needs to be pushed back all the way to make room for the new brake pads to seat in properly. You can try using a G-clamp to move the calliper back but in most cases, this may not work. One solution is to but the brake calliper back onto the disc as it was originally mounted. The 2 star bolts needs to be fully tightened into place.
A thick wood stick or even a metal crow bar can be inserted into the gap between the brake disc and the hydraulic unit of the calliper and force exerted in a way that the inside of the brake disc smooth surface does not bear the impact. It's extremely important that no sensitive parts are damaged whilst exerting the force to push the calliper unit back.
Once the calliper hydraulic unit has been pressed all the way back into its original place, the brake calliper can be mounted off the brake disc so the new brake pads can be inserted into place.
The new brake pads must be setaed in properly on the discs and the brake calliper should be tightened properly. The brake pedal should be depressed a few times so the pads get seated properly in their place and the calliper hydraulic unit should be seen to be pressing against the pads like it should.