Manufacturer Codes: 21

Fault, DTC 21 Test Point 11

Rpm signal from DME control module
Signal implausible

Possible causes, elimination, notes

Fault effect:
Reduced driving program.

NOTES:
- The DME control module signals a fault directly to the Tiptronic control module via a data lead (CAN bus).
- The rpm signal can be checked with the Porsche System Tester 2 (Actual values/Rpm).

1. Check rpm signal with the tester.
2. Read out fault memory of the DME control module and remedy the fault according to the DME test plan.
3. Check wiring from Tiptronic control module connector pin 86 (or 85) to the DME control module connector pin 86 (or 85) for open circuit, short to ground and short to B+.