Possible causes, elimination, notes
NOTE:
The Tiptronic control module (pin 25) is connected with instrument cluster (pin II/17) via a serial data lead.
Specification:
- Signal type = PWM
- Frequency = 50 Hz
- Level = 0 ... 12 V
Signal coding:
NOTE:
There is no fault if the pulse width is 70 % with the engine running and with the selector lever in position "P".
SIGNAL CODING
| Actual gear | 1 | 2 | 3 | 4 | 5 |
|---|---|---|---|---|---|
| Pulse width | |||||
| in "D" | 10% | 20% | 30% | 40% | 50% |
| in "M" | 15 % | 25 % | 35 % | 45 % | 55 % |
- Test the PWM signal with an oscilloscope.
- Check wire from Tiptronic control module connector pin 25 to the instrument cluster connector II (white) pin 17 for open circuit, short to ground and short to B+.