Checking Vehicle Height

Information 

On vehicles with air suspension, the vehicle must be set to normal level.

• Measure and adjust at this position only. 
• Do not get into or out of the vehicle while and after setting Normal level for suspension alignment. This can give false alignment results. 

Information 

If the control unit or one of the level sensors was replaced, calibration must be performed.

> 430115 - CALIBRATING THE LEVELLING SYSTEM

1. Only for vehicles with air suspension system: 

   Adjust vehicle to normal level:

   1. 1.1 Drive the vehicle onto the wheel-alignment platform, stop the engine and move selector lever to position P  .
   2. 1.2 PIWIS Tester  must be connected to the vehicle and switched on.
   3. 1.3 Switch on ignition.
   4. 1.4 Select level control system/PASM in the control unit overview  .
   5. 1.5 Switch to Drive links/checks  and select Adjust vehicle level  .
   6. 1.6 Select the value Low Level 1  and press F8 to start in order to adjust the vehicle to low level.
   7. 1.7 Once low level is reached, select the value Normal level  and press F8 to start in order to adjust the vehicle to normal level.
2. Only for vehicles with air suspension system: 

   Switch off the level control system.

   1. 2.1 PIWIS Tester  must be connected to the vehicle and switched on.
   2. 2.2 Switch on ignition.
   3. 2.3 Select level control system/PASM in the control unit overview  .
   4. 2.4 Switch to Drive links/checks and select Activate/deactivate vehicle  .
   5. 2.5 Select Deactivate level control system (permanently)  and press F8 to start in order to switch off the levelling system.
   6. 2.6 Switch off ignition.
3. Compress the vehicle at front and rear axles by about 25 mm  2-3 times and allow it to spring back freely.
4. Measure the standing height to the lower edge of the -X-  mudguards on all four wheels of the vehicle.

   Fit measuring tape -1- on - the outer diameter of the quick-clamping unit at the -2- top. 

   Courtesy of PORSCHE CARS NORTH AMERICA, INC.

   Example of height dimension of quick-clamping unit/lower edge of wing

   1. 4.1 Make sure that the bonnet is closed before taking measurements to prevent measurement errors.
   2. 4.2 Measure from the lower edge of the mudguard to the outer diameter of the quick release unit at the top, measure -X-  .
   3. 4.3 Add the -X-  radius of the quick-clamping unit 32.5 mm  to this measured dimension.

      Sample calculation: 

      Measured star gauge X= 382 mm; radius quick clamping unit = 32.5 mm

      X + radius of quick-clamping unit = vehicle body height 

      382 mm + 32.5 mm = 414.5 mm

5. Only for vehicles with air suspension:  As soon as at least one of the measured height values does not correspond to the required height values, the levelling system must be calibrated.

   Required height values:

   > 4495TW - SETTING VALUES FOR VEHICLE MEASUREMENT 

   1. 5.1 Calibrate the levelling system:

      > 430115 - CALIBRATING THE LEVELLING SYSTEM