GF32.33-D-2009H Manual Height Adjustment Function
GF32.33-D-2009H Manual Height Adjustment Function
- with CODE (CE2) Rear air suspension
Function requirements
^ Circuit 15 ON
^ Vehicle speed <2 km/h
^ Manual mode activated
^ Model 639: A side door, rear-end door or liftgate is open
^ No overvoltage or undervoltage
Overvoltage present when the voltage is > 16.2 V.
Undervoltage is present when voltage is < 9 V.
General
The manual mode is activated by pressing the raise/lower electronic level control switch (S77/2) (for model 639 raise or lower level control switch (S77)) for t = 1.5 s.
This is indicated by the electronic level control warning lamp (A1e5) in the instrument cluster (A1) flashing on and off.
The mode is also indicated on model 639 by the indicator lamp in the lock level control switch (S77/1) flashing on and off.
The "Manual height adjustment" function consists of the following subfunctions:
^ Behavior with Circuit 15
^ Raise the rear axle.
^ Lower the rear axle
^ Automatic deactivation of electronic level control (ELC [ENR]) system
Behavior with Circuit 15
If Circuit 15 is deactivated in manual mode, then reactivated and the vehicle speed is below 2 km/h, the electronic level control system remains in the manual mode. This indicated by the electronic level control warning lamp in the instrument cluster flashing on and off.
The mode is also indicated on model 639 by the indicator lamp in the lock level control switch (S77/1) flashing on and off.
At a vehicle speed of > 2 km/h an automatic switch is made to the automatic mode. At "circuit 15 OFF" status the electronic level control system switches to manual mode. The ELC [ENR] warning lamp in the instrument cluster and in model 639 the indicator lamp in the lock level control switch are, however, not activated. The raise/ lower electronic level control switch (for model 639 raise or lower level control switch) and the lock electronic level control switch (S77/1) are deactivated by closing the sliding doors, rear-end doors, liftgate (model 639).
Raise the rear axle.
If the level of the vehicle's rear axle is below the normal level (0 mm) and if the raise/lower electronic level control switch (for model 639 raise or lower level control switch) is pressed briefly in the upper area (to raise), then the vehicle's rear axle level is automatically raised to the normal level (0 mm).
The raise/lower electronic level control switch (for model 639 raise or lower level control switch) does not need to be held. Another brief press of the raise/lower electronic level control switch (for model 639 raise or lower level control switch) in the upper (to raise) or lower area (to lower), or a brief press of the lock electronic level control switch, interrupts the automatic raise process. If during the automatic raising process, the sliding doors, rear-end doors, liftgate (model 639) are closed, then the automatic raising process is continued to the normal level (0 mm).
If the vehicle's rear axle level is raised beyond the normal level (0 mm), then the raise/lower electronic level control switch (for model 639 raise or lower level control switch) in the upper area has to be pressed and held.
When the raise/lower electronic level control switch (for model 639 raise or lower level control switch) is released the raising process is immediately interrupted. The vehicle is raised to the upper permissible level (+40 mm) only.
Lower the rear axle
Pressing and holding the raise/lower electronic level control switch (for model 639 raise or lower level control switch) in the lower area lowers the vehicle's rear axle until the raise/lower electronic level control switch (for model 639 raise or lower level control switch) is released.
If the vehicle's rear axle level drops below a specific value, the vehicle will then touch down on the additional rubber spring integrated into each air spring bellows. This then restricts the suspension comfort.
Automatic deactivation of electronic level control system
Automatic deactivation of the electronic level control system takes place under the following conditions:
- When a fault was detected
- "Circuit 61 OFF" and weak battery (G1)
- In order to protect the level control compressor (A9/1) against overheating as a result of repeated raising or lowering of the vehicle rear axle
- When the vehicle rear axle is raised or lowered on one or both sides quickly enough
- When the vehicle stops for t = 80 s on a vehicle lift (lowering time-out period)
- When the Controller Area Network bus class B (interior) (CAN-B) is in quiescent state (sleep mode)
