S80 L5-2.5L Turbo VIN 59 B5254T2 (2004)
There are two sensors in the fuel tank which transmit signals about the fuel level to the rear electronic module. The rear electronic module (4/58) sends
the values on to the driver information module (5/1), which receives the signals, interprets them and displays the fuel level on the fuel gauge. When the
fuel level is low a yellow lamp lights to inform the driver.
The fuel gauge is not sensitive to rapid change. This is to prevent incorrect values being displayed when cornering or driving on slopes for example.
Speedometer
The speedometer displays the actual speed the car is traveling at.
Information about the vehicle speed comes from the speed sensor which is connected to the brake control module (called the ABS module on cars up to
and including model year 2001) and the transmission control module (TCM)
(4/28). The brake control module (4/16) and the transmission control module (TCM) calculate an average speed based on the signals sent from the two
front wheels by the speed sensors. The calculated speed signal is then transmitted to the central electronic module (CEM) (4/56) from the brake control
module and the transmission control module on the high speed section of the Control Area Network (CAN). Depending on the quality of the signal, the
central electronic module uses the signal from the brake control module or the transmission control module (TCM). The central electronic module then
transmits this data on to the driver information module (5/1) where it is displayed.
Only cars with automatic transmission have a transmission control module (TCM). In cars with manual transmissions, the speed signal is transmitted to
the central electronic module by only the brake control module on the high speed section of the Control Area Network (CAN).
Tachometer
