If the caravan still looks tilted after levelling has finished, what could be the reason?
If the system says level but the vehicle looks tilted, suspect the sensor reference first. Check the fixing and renew the Tare on flat ground.
If the system levels to a precision of 0.025 degrees and the vehicle still looks tilted to the eye, the first suspicion is the reference of the ASX103 inclination sensor. The sensor measures tilt relative to its own mounting plane; if that is not exactly parallel to the chassis, the system gives a result that is right against its own reference and wrong against the vehicle. The remedy is to check the fixing of the sensor and to zero the reference with Tare.
First separate what you are measuring
What the system measures is the plane the sensor sits on, not the body of the caravan. These two planes are aligned during installation; when the alignment is disturbed the system carries on working without a fault but works against a wrong reference. That is why the first step is not to look for a fault but to test whether the tilt calibration is still valid.
Do not confuse resolution with accuracy either. That the app can display a very small figure in degrees does not mean that figure is right relative to the real plane of the vehicle; the number on the screen is always relative to the sensor's own reference. If the reference is wrong the zero it shows is wrong too, and the system cannot notice this on its own.
Possible causes and checks
- Tare not performed or disturbed: Tare defines the system's zero reference. If the sensor has moved or the reference was not taken properly at first installation, the vehicle should be checked on flat ground with an independent spirit level and the Tare renewed.
- Sensor fixing loosened: The ASX103 may have rotated or tilted slightly with vibration. Check the screws and the surface contact; the surface the sensor sits on must be rigid and parallel to the chassis plane.
- Ground settling: On soft ground one of the jacks may have sunk in after levelling finished. Put a plate under it and repeat the procedure.
- Interior loading: Heavy load gathered on one side inside the vehicle can compress the suspension and create a visual tilt in the body; this does not contradict the level measurement.
- Difference between body and chassis: Door and cabinet alignments do not always match the chassis plane exactly, because of manufacturing tolerances. The tilt you perceive by eye may come from there too.
From symptom to cause
| Symptom | What to look at first | Verification |
|---|---|---|
| The app shows zero, the spirit level shows a tilt | Tare reference | Repeating Tare on flat ground |
| The deviation is in the same direction at every stop | Sensor fixing | Checking the screws and the surface contact |
| It tilts over time after levelling | Ground settling | A plate under the jack, procedure repeated |
| The tilt is felt on one side only | Interior loading | Redistributing the load and measuring again |
What Tare does not solve
Tare defines a reference; it does not remove a mechanical restriction. If one of the jacks has run to the end of its stroke and cannot extend further, the system cannot reach the level point; in that case you change the parking spot or raise the ground under that jack. In the same way, if there is chassis torsion, one corner of the chassis is level and another is not, and a single sensor cannot see this. If you carry out Tare on sloping ground you make the error permanent; the reference is always taken on flat ground.
Verification method
Put an independent spirit level on the chassis at the point you took as reference and compare it with the numerical degree value in the application. If the two agree, the problem is not in the sensor but in perception or in loading. If they do not agree, the Tare must be repeated. Always measure from the same point and mark that point; measurements taken from different points cannot be compared with each other. Repeat the measurement both lengthways and crossways: a spirit level reading taken in one direction only can hide a deviation on two axes.
The full topic: RV automatic levelling guide