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Electrical - Battery Disconnect Switch Information

23/08

ENU 0101

Jul 15, 2008

Battery Disconnect Switch: 10 Seconds Waiting Time

Vehicle type:
Cayenne/Cayenne S/Cayenne GTS/Cayenne Turbo

Model Year:
As of 2008

Concerns:
Actuating the main power supply switch, referred to below as battery disconnect switch:
- When transporting vehicles (Porsche factory -> Porsche dealer]
- For vehicles in stock.

INFORMATION:
Battery disconnect switch in the vehicles is set to "open":
The engine can no longer be started once the battery disconnect switch is set to be "closed".

The reason for this is that the amount of time for completing the previous step (= time between switching ignition off and setting the battery disconnect switch from "closed" to "open") was less than 10 seconds.

The system continues to store data in the DME control unit for a few seconds after the ignition is switched off. If this data storage process is interrupted by disconnecting the power supply, it will no longer be possible to start the engine again when the power is restored. If this happens, the DME control unit must be programmed using the PIWIS Tester 9718.

If communication with the control unit cannot be established using the PIWIS Tester, replace the DME control unit.

Action Required:

ATTENTION
Voltage drop
- Risk of irreparable damage to DME control unit.
- More time and effort required for programming DME control unit.
--> When transporting vehicles for ship, rail and/or truck: allow a waiting time of approx, 10 seconds between switching ignition off and setting the battery disconnect switch to "open".
--> For stock vehicles with a battery disconnect switch: allow a waiting time of approx, 10 seconds between switching ignition off and setting the battery disconnect switch to "open".






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