On vehicles fitted with an anti-theft alarm system, illumination of the front and rear interior lamps is controlled by the anti-theft alarm ECU. The anti-theft alarm ECU monitors the condition of all the doors, illuminating the interior lamps when any door (including the tail door) is opened. The anti-theft alarm ECU also features a time-out function, which extinguishes the lamps after 8 minutes if any of the doors are left open. The anti-theft alarm ECU will also illuminate the interior lamps if the vehicle is disarmed using the remote handset.
The interior lamps can also be controlled manually, by moving the three position switch mounted in the lamp assembly to the 'On' position.
NOTE: The time-out function is by-passed if the three position switch is moved to the 'On' position.
Operation
Power Distribution
Feed from the positive battery terminal (C0192) is supplied to fusible link 1 and fuse 7 of the under seat fuse box (C0632) on an N wire. Fuse 7 (C0574) provides a constant battery feed to the anti-theft alarm ECU (C1979 on LHD, C0061 on RHD) on a PN wire.
Fusible link 1 is connected in series with fusible link 2, which is also located in the under seat fuse box. Fusible link 2 (C0570) is connected to fuse 30 of the passenger compartment fuse box (C0595) by an NK wire. Fuse 30 (C0580) provides a constant battery feed to the following on PN wires:
- The front interior lamp (C0355)
- The rear interior lamp (C0356) – 90 vehicles only
- The rear interior lamp (C0357) – 110 vehicles only.
Door Switches
The anti-theft alarm ECU (C1979 on LHD, C0061 on RHD) monitors the condition of the door switches as follows:
- The driver door switch (C0266 on LHD, C2007 on RHD) on an SW wire
- The front passenger door switch (C0265 on LHD, C0106 on RHD) on a PU wire
- The LH rear door switch (C0104) on a PU wire The RH rear door switch (C0108) on a PU wire
- The tail door switch (C0615) on a PU wire – 90 Station Wagons only
- The tail door switch (C1992) on a PU wire – 110 Station Wagons only
- The tail door switch (C1993) on a PU wire – 90 Hard top vehicles with Central Door Locking (CDL) only
- The tail door switch (C1994) on a PU wire – 110 Hard top vehicles with CDL only.
When any of the doors are opened, the relevant door switch contacts close creating an earth path. When the anti-theft alarm ECU registers an earth, it illuminates the interior lamps.
Front Interior Lamp
With the lamp switch in the central position, current flows across the bulb and switch contacts (C0355) to the anti-theft alarm ECU (C1979 on LHD, C0061 on RHD) on a PW wire. When the anti-theft alarm ECU registers an earth path via the door switches, it provides an earth path to illuminate the front interior lamp.
With the lamp switch in the 'On' position, current flows across the bulb and switch contacts (C1210) to earth on a B wire.
With the lamp switch in the 'Off' position, current cannot flow across the bulb and switch contacts.
Rear Interior Lamp – 90
Models With the lamp switch in the central position, current flows across the bulb and switch contacts (C0356) to the anti-theft alarm ECU (C1979 on LHD, C0061 on RHD) on a PW wire. When the anti-theft alarm ECU registers an earth path via the door switches, it provides an earth path to illuminate the front interior lamp.
With the lamp switch in the 'On' position, current flows across the bulb and switch contacts (C1209) to earth on a B wire.
With the lamp switch in the 'Off' position, current cannot flow across the bulb and switch contacts.
Rear Interior Lamp – 110
Models With the lamp switch in the central position, current flows across the bulb and switch contacts (C0357) to the anti-theft alarm ECU (C1979 on LHD, C0061 on RHD) on a PW wire. When the anti-theft alarm ECU registers an earth path via the door switches, it provides an earth path to illuminate the front interior lamp.
With the lamp switch in the 'On' position, current flows across the bulb and switch contacts (C1991) to earth on a B wire.
With the lamp switch in the 'Off' position, current cannot flow across the bulb and switch contacts.