Ignition interlock (where fitted)

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2004 Land Rover Discovery, 2003 Land Rover Discovery, 2002 Land Rover Discovery, 2001 Land Rover Discovery, and 2000 Land Rover Discovery. However, it is still accessible from the selected car via links, so may be relevant.

On automatic gearbox models, when the ignition key is inserted in the ignition switch, the ignition key-in switch contacts close to supply a signal to the BCU to indicate the presence of the key in the switch and provide a supply feed to the ignition interlock solenoid. If the gear selector lever is in a position other than Park, or the 'transfer box neutral selected' is on, the BCU will supply an earth path to complete the ignition interlock circuit and cause the interlock solenoid to be engaged. With the interlock solenoid engaged, removal of the ignition key is prevented. The BCU will open the circuit, to allow removal of the ignition key, only when the gear selector lever is in the Park position and the transfer box is in either high or low range.

The ignition key interlock option can be programmed in one of three states dependent on market/ customer requirements, these are:

Option 1- not fitted.
Option 2 - normal operation.
Option 3 - inhibit transfer box.

The BCU checks the status of the following inputs to determine the logic action for operating the ignition key interlock solenoid:

Transfer box neutral selected.
Gearbox state.
Transit mode.

When the transit mode is on, the ignition key interlock solenoid is off.