Disconnecting the speed input temporarily makes the Navigation ECU think the car is stopped. After between 20 to 60 seconds, the ECU gets updates from the GPS satellites and knows that the car's position has changed and so makes most menus unavailable again. You then have to push the button on, then back off and the cycle starts over. For a simple installation, you can just install an on/off switch between the speed input wire and the Nav ECU.
I got tired of being interrupted by the Nav ECU when I'm trying to find a restaurant, so I modified the mod. On the first pole of the pushbutton switch below, the COM and NC is connected between the speed input wire and Nav ECU as described above. On the other pole, the COM is +12V (cig lighter is convenient) and NO goes to the + of the Altronix 6062 timer. The other timer connections are: - to vehicle ground, C to speed input wire and NO to Nav ECU (pin 5, connector A). The dip switch settings are: 1 ON, 2 ON, 3 ON, 4 OFF. The pot is set to about 20 (seconds). Jumpers 1 and 2 are both cut. The TRG connection is not used since we have the timer set to trigger on first connection and repeat every 20 seconds. By now you probably see what's going on. With the pushbutton off, the timer is off and the speed input wire is connected, so the NAV works per factory specs. Pushbutton on and the speed input is disconnected from the Nav ECU and the timer is turned on. At the end of 20 seconds and every 20 seconds after that, the timer closes the C and NO connection (connects the speed input wire to the Nav ECU) for a 1 second pulse. That cycle continues until you push the button back to the off position.
