Driver/Vehicle Information Display: Description and Operation
CIRCUIT OPERATIONThe Driver Information Center (DIC) system uses the following components to provide the driver with vehicle systems information.
1. Driver Information Center (DIC)
2. Lamp Monitor Module (STE only)
3. Headlight Switch
4. Lamp Driver Module (STE only)
5. Engine Control Module (ECM)
6. Fuel Level Sender
7. Door Handle Switches (4) (STE only)
8. Hood Ajar Switch (STE only)
9. Trunk Lid Ajar Switch (STE only)
10. Washer Fluid Level Switch (STE only)
SIGNAL PROCESSING
The DIC contains the compass electronics and receives input directly from the above listed components. The Fuel Gauge Sender input is directly related to the amount of fuel in the tank.
The Driver Information Center also receives information directly from the Engine Control Module (ECM). The ECM sends Fuel Gauge usage information over the serial data line and vehicle information from its speed signal output. This information is used by the DIC to compute range, average speed, average fuel economy and instant fuel economy. This information is also used by the DIC service reminder.
On the STE, the DIC receives serial data information concerning discrete inputs from the Door Handle Switches, Hood Ajar Switch, Trunk Lid Ajar Switch, Washer Fluid Level Switch from the Lamp Monitor Module. The DIC also receives a discrete input directly from the Lamp Driver Module for and ABS problem. These inputs are either switched to ground or opened to ground by the respective switches or module. A ground signal always indicates conditions that require a display message and/or its corresponding graphic be illuminated.
Also on the STE the DIC receives serial data information concerning lamp outages from the Lamp Monitor Module. The Lamp Monitor Module monitors the lamps by measuring voltage drops across its internal resistors. If the lamps are functioning normally, there will be a certain amount of voltage dropped across these internal resistors. If there is a lamp outage, there will be a smaller or zero voltage drop across the resistor. The Lamp Monitor Module detects this and sends the appropriate lamp outage information to the DIC over the data lines.
ILLUMINATION
The Driver Information Center receives incandescent button illumination from the Headlight Switch by CKT 8. The vacuum fluorescent display dims to the current dimmer setting when it sees voltage on CKT 9. This signals the display to look at the light switches dimmer, CKT 230 for the exact level to dim the display.