FixVault

Fault code 0849: Diagnosis/troubleshooting

NOTE: Visual inspection: In the next troubleshooting section, please check first that the affected pins on the rear convenience system control unit plug connection are neither damaged nor corroded. The wiring and plugs of the affected components must also be checked for external damage and proper contact. Repair damaged or corroded pins if possible, otherwise replace affected pins. Repair or replace damaged wires.
NOTE: Sporadic faults: In the event of faults that occur sporadically, the wiring positions that are linked to moving parts on and in the vehicle must be checked for each system. Various statuses that can cause faults must be simulated with the help of the wiring diagram.
NOTE: Battery voltage: A battery voltage of between 11.4 and 14.5 V is required for the following troubleshooting procedure. This must be checked and provided, if necessary. On the vehicle electrical system, the voltage to the fuse (input side) must be guaranteed.
NOTE: 'Implausible signal' → This fault is detected if the key is not in the ignition starting switch and the following conditions are met:

or

WORK INSTRUCTION CHART

Work instruction Display OK If not OK
1 Check fault memory in rear convenience system control unit for further faults Fault code '576 terminal 15' present
=> Work through further faults
Go to step 2
2 Check KESSY control unit for faults Faults present
=> Work through faults
Go to step 3
3 Check S contact on ignition starting switch
  • Use the Porsche System Tester II No. 9588 to switch to the KESSY control unit
  • Use the Porsche System Tester II No. 9588 to switch to the menu 'Actual values/S contact'
  • Remove/insert ignition key
Actual value changes accordingly
Go to step 4
Continue troubleshooting, refer to KESSY/IMMOBILISER -- 9PA_CAYENNE .
→ End
4 Check vehicle speed in instrument cluster
  • Use the Porsche System Tester II No. 9588 to switch to the instrument cluster
  • Use the Porsche System Tester II No. 9588 to switch to the menu 'Actual values/Vehicle speed'
  • Vehicle not moving
0 km/h
Go to step 5
Continue troubleshooting for instrument cluster, refer to FAULT OVERVIEW .
→ End
5 Replace rear convenience system control unit → End