Test Point 13 - Speed Sensor
TEST POINT 13 - Speed sensor (transmission) - Fault code 36Possible Causes, Elimination, Remarks
Tiptronic warning lamp comes on, transmission is in emergency mode.
Detectable faults: Open circuit/Short to ground/short to positive, loose connection
NOTE:
- Check with Tester 9288 (actual values). Store faults as of engine speed = 2800 rpm
- The sensor transmits the transmission speed. The Tiptronic control unit compares it to the wheel speed.
1. Pull connector off Tiptronic control unit.
- Measure resistance between pin 2 and pin 38. Nominal value approx. 1.1 k ohm
- Check that pin 2 and pin 38 are free from shorts to ground.
2. Also pull off connector from speed sensor, transmission.
- Check for continuity at Tiptronic control unit connector pin 2 to speed sensor connector pin 1
- Check for continuity at Tiptronic control unit connector pin 38 to speed sensor connector pin 2
- Short to ground pin 2 and pin 38 to pin 7 (ground)
- Pin 2 and pin 38 to pin 20 (screening)
- Short to positive pin 2 and pin 38 to pin 1 (positive)
NOTE: If it is to be assumed that intermittent faults linked to the output speed occur, the screening connection at pin 20 should be checked after opening the connector housing.
Possible transmission faults: Oil strainer clogged, air intake if oil starvation occurs etc., power transmission interrupted. Oil level low.