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BoxxerSix BoxxerSix is offline
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Join Date: Jun 2006
Location: Ballston Spa, NY
Posts: 528
Originally Posted by TimT View Post
No the calibration resistor come with the sensor.Bosch installs these.....

The manufacturing variation problem, which results in sensors of varying sensitivities (differing pump currents for the same Lambda), is solved by adding a calibration component. A resistor (Rcal) is laser trimmed after the sensor is constructed and tested. The laser burns away material and increases the value of the resistor until a standard Ip current is produced at a known Lambda value. If this circuit is reproduced in the controller itself then each sensor will be automatically calibrated without further calibration. Obviously, as each sensor is factory calibrated, and the calibration component is usually in the sensor connector itself, if someone removes the connector, then the sensor has become uncalibrated!

Ok now that makes sense to me. Never really looked at the other sensors with other widebands, it was just brought to my attention on the AEM units and I assumed it was an AEM thing. DOH! Guess I should pay more attention to my tools and electronics here, hahah!.
Adam Hennessy
Old 05-08-2008, 04:13 AM
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