Coolant temperature indicator
Normal mode

Block diagram


Operating phase when +APC is on
The coolant temperature indicator shows the driver the engine coolant temperature using a needle gauge.
The engine coolant temperature information comes from the sensor. The engine ECU encodes the measurement in a CAN frame and sends it to the BSI. The BSI converts the information into a VAN Comfort frame and sends it to the instrument cluster.
Special case: engine coolant temperature warning
The engine ECU determines the engine coolant temperature warning based on the defined threshold (118 °C). The engine ECU sends the information to the BSI, which transmits it to the instrument cluster.
Warning lights V12 and V22(*) come on.
(*) depending on equipment level.
Display
The coolant temperature is converted into needle angle according to the following diagram:

Level 1 instrument cluster with manual gearbox

Level 2-3 instrument cluster with manual gearbox and level 1-2-3 with automatic gearbox

Degraded mode
If a communication error occurs on the network or an invalid value is received, the needle returns to its rest position 5 seconds after the fault appears. During this time, the last value received is displayed.
Test yourself
A quick Citroen C5 Aircross quiz: every answer comes with an explanation and a link to the manual page.