Power Supply; Operation; Test Function - Bahco BELT10 Gebrauchsanweisung

OPERATING MANUAL

POWER SUPPLY

Connect the red clip to the battery's (12V) positive terminal and the black clip to the negative terminal.
If the connection is correct, the LED indicator marked "bat" should light in green color. If this indicator lights red, is because an
inverted connection.

OPERATION

Once the tester is correctly connected to the battery, connect the piercing probe clip of the tester to the corresponding cable of
the lambda sensor under test. The readings on the tester will be scaled automatically as a function of the voltage in the sensor's
cable. The method to recognize the lambda sensor cables is as follows:
1 - If the connected cable corresponds to the HEATER POSITIVE SUPPLY, then the light indicator marked "12V" will light.
2 - If the connected cable corresponds to the HEATER GROUND CONNECTION, then the light indicator marked "0V" and the
bottom led in the curve will light. Exception: when the ground connection is made through a semiconductor element (as a
transistor in the ECU), it is possible that the light "0V" remains off, and the lighting indicator in the curve array could be the
second or third from the bottom. To ensure in both cases the cable connected corresponds to ground, it is advised to press the
button "TEST ++" and check that the lighting indicator does not change or change only by one step.
3 - SIGNAL GROUND CONNECTION: The same as said in the previous paragraph. In some vehicles, the signal ground may be
connected to the vehicle's ground through a resistor. In this case, when the button "TEST ++" is pressed, the inferior light of the
curve would go off, and the superior on.
4 - SENSORS REFERENCE VOLTAGE (this only applies for the sensors of Titania type). If the connected cable is the 5V
reference, then the light "Ti 5V" will light. For systems where the reference voltage is of 1V, then the upper indicator of the curve
will light. In both cases the reading must be steady and continue.
5 - SENSOR OUTPUT SIGNAL: This is the only one that, when the lambda sensor works correctly, experiments variations of
voltage. When the sensor reaches its working temperature, the output voltage swings following the oxygen contents in the
exhaust gases.
To test the correct condition of a lambda sensor, there should be an oscillation between 0.1 and 0.9V (for lambda sensors of
1V). This corresponds to a progressive lighting of the indicators in the curve, up and down and vice-versa (red-yellow to
yellow-red). The frequence of oscillation depends of many factors (engine size, speed of response of the ECU, engine speed,
sensor distance from the exhaust, etc.), but a frequence of several times per seconds at a stabilized speed of 2000 - 2500 rpm,
may be considered correct.
In case that the readings result in fixed values (no oscillation), or very slow oscillations, check that the connection to the sensor
cables is correct, and the engine has reached a normal working temperature. After ensuring that, and before disposing of the
sensor, it could be wise to use the TEST function to check the correct response of the ECU, as follows:

TEST FUNCTION.

WARNING! Be aware that a test simulation performed for a long time may cause the ECU to store an error code. It is
recommendable not to prolong the test for more than five seconds for vehicles equipped with that type of ECUs.
The test function allows to check the ECU's response, by simulating artificially the rich or lean condition while checking that the
injection system tends to increase or decrease the mixture in an opposite way to the performed simulation. The injection
system will tend to enrich the mixture when a lean condition is simulated, and vice-versa.
When pushing the buttons "TEST ++" (simulating rich) or "TEST --" (simulating lean), the TEST indicator will light, and the
simulated voltage will be forced in the output cable of the sensor (provided that this is the correct cable connected to the tester).
Then check the response of the injection system.
SNA Europe SAS (Group Headquarter)
Allée Rosa Luxembourg - 95610 Eragny sur Oise - France
www.bahco.com
BELT10