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Discussion Starter #1
In looking for a discussion regarding the test and evaluation of Adaptive headlight errors; I found that only Pelican Parts had testing info. However, it required back-probing the cable while under the car.
So, I decided to come up with a way to bench test the sensors.
First of all; the level sensors are tied into the headlight leveling system. There are two level sensors, one sensor is located attached to the front suspension on the passenger side of the car and the other on the same side at the rear.
Together they determine the height the headlights are pointing.
A faulty sensor may or may not through a fault code.
The sensors are NOT just a simple potentiometer. But rather an active circuit that produces a voltage output proportional to the height of the car.
In order to bench test the sensor; it is necessary to activate the sensor circuit.
To do the test, you will need:
1. A 5 volt power source. Bench supply, batteries, etc.
2. A multi-meter. For this test I prefer a good old analog meter. A digital will work too but it's harder to follow smooth movement...
3. 3 pieces of bus wire + 3 small shrink tubes.
4. Some alligator jumpers to hook things up.
1. Shrink the tubing down on each of the three sections of bus wire, leaving enough wire exposed to connect an alligator clip to it.
The opposite side of the wire should be made flush with the shrink tube.
Leave that end of the shrink only partially shrunk to allow it to be slipped over the sensor pins.
2. While supporting the sensor in a vice or somehow, Connect the 5 volt power source to the sensor.
Just slip the bus wire with shrink tubing over the sensor pins...
Negative to Pin #1
Positive to Pin #5
3. Connect the positive lead of the meter to Pin #4 of the sensor and the negative meter lead to the negative of the power source.
1. As you rotate the sensor arm throughout a full 360 degrees of rotation; the voltage at pin #4 should swing between approx. 0.5 volts and 4.6 volts. It should swing two time for the 360 degrees revolution.
2. Look for a smooth voltage change as you move the arm slowly. If it jumps around, the sensor is probably faulty.
3. I like to rotate the sensor arm through its full rotation several times to insure its smooth operation.


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