PRE-RELEASE
Rheostat
| Rheostat |
| General |
The rheostat is integrated in the main lights switch and gives the SID control module information on the rheostat setting selected by the driver.
The rheostat is a potentiometer which is supplied with +5 V via pin 23 of the control module. The rheostat is grounded through pin 24.
The voltage across the resistance, which is built into the SID unit, is proportional to the rheostat resistance, see fig. The SID control module uses the value to calculate the display illumination value.
Information on the rheostat level is sent as bus information, Rheostat level, unit (%). See
| Diagnosis |
An open circuit causes diagnostic trouble code B1736 to be generated.
A short-circuit to ground does not result in a diagnostic trouble code, the rheostat level is at “max” and cannot be altered with the rheostat.
A short-circuit to B+ will destroy the rheostat.
