When calibrating the air suspension the vehicle is going to move up and down. It is very important that neither persons or equipment are in the area around or under the vehicle's frame as squeezing injuries easily can occur.
Note:
The correct setting measurements for normal drive level can be found in the charts below.
If the drive level outside the permissible range is used the vehicle will not accept the drive level and fault codes is stored.
Test prerequisites:
Ignition on with external air or the engine running.
The vehicle should be unloaded.
The vehicle should be standing on level ground.
The lift axle should be lowered if fitted.
Make sure that the tag axle/load transfer and any alternative drive level are switched off.
To avoid tensions in the chassis during calibration the parking brake must be released first. Lock the vehicle with blocks in front of and behind the wheels before commencing work.
Procedure:
Maximum level
Raise the vehicle to the shock absorbers upper mechanical stop, front and rear, using the control box.
Calibrate the maximum level.
Minimum level
Lower the vehicle to the shock absorbers bump stop, front and rear, using the control box. Check that the lowering is not limited, for example because of creasing of the bellows.
Calibrate the minimum level.
Normal drive level
Set normal drive level, front and rear, with the control box. The correct setting measurements for normal drive level can be found in the charts below.
Calibrate the normal drive level.
End the diagnostic session. Then turn off the ignition for at least 5 seconds to apply the new settings.
Information concerning adjustment to bellows height generation 2.
Chassis height.
There are three different chassis heights that influence the heights for calibration.
N means Normal, for example 4x2 N.
L means Low, for example 4x2 L.
E means Extra low, for example 4x2 E.
Front axle.
The front axle´s point of impact decides what bellow heights that should be chosen at front calibration.
AMA 860 point of impact 170mm.
AMA 740 point of impact 112mm.
AMA 920 point of impact 82mm.
The bellow heights at front are measured between the frame´s underside and the lower edge of the bellow´s lower roller body.
Chassis | Bellows height | Front axle | Drive level +/- 10 mm | Maximum level +/- 10 mm | Commentary |
4x2N 6x2N 6x4N 6x2/4N 8x2/4N 6x2*4N 8x4*4N | Normal | AMA 860 | 317 | 537 | - |
4x2N 6x2N 6x4N 6x2/4N 6x2*4N | Low | AMA 740 | 265 | 452 | - |
8x2N 8x4N 8x2*6N | Normal | AMA 860 | 317 | 477 | - |
8x2N 8x4N 8x2*6N | Low | AMA 740 | 265 | 425 | - |
4x2L 6x2L 6x2*4L | Low | AMA 860 | 285 | 452 | Produced before February 2000 |
4x2L 6x2L 6x2*4L | Low | AMA 860 | 265 | 452 | Produced after February 2000 |
6x2/4L | Extra low | AMA 860 | 218 | 328 | - |
4x2E | Extra low | AMA 860 | 218 | 328 | - |
Rear axle.
The type of rear axle bridge decides which type of bellow heights to choose at calibration at the rear. Measurements on vehicles with supporting axle shall be done with the axle lowered.
ADA 1300.
ADA 1500.
Tandem boggy.
Another factor that influences the calibration is the generation of the rear axle suspension.
Generation 1 has the shock absorbers at the inside of the frame.
Generation 2 has the shock absorbers at the outside of the frame.
The rear bellow height is measured between the rear axle bridge´s upside and the underside of the frame, with the supporting axle lowered.
Chassis | Rear axle | Drive level +/- 10 mm | Maximum level +/- 10 mm | Commentary |
4x2N 6x2N 8x2N 6x2*4N 8x2*6N | ADA 1100/1300 | 128 | 288 | - |
4x2N 6x2N 8x2N | ADA 1500P/1501P | 122 | 282 | - |
6x4N 8x4N 8x4*4N | ADA 1100/1300 | 128 | 233 | - |
6x2/4N 8x2/4N | ADA 1100/1300 | 128 | 257 | - |
8x2/4N | ADA 1500P/1501P | 122 | 251 | - |
4x2L 6x2L 6x2*4L | ADA 1100/1300 | 101 | 288 | Produced before February 2000 |
4x2L 6x2L 6x2*4L | ADA 1100/1300 | 70 | 225 | Produced after February 2000 |
6x2/4L | ADA 1100/1300 | 96 | 242 | - |
4x2E | ADA 1100/1300 | 78 | 239 | - |