PRE-RELEASE
Coolant level sensor
| Coolant level sensor |
| General |
The coolant level sensor consists of a round magnetic float which moves up and down along a hollow column attached to the bottom of the expansion tank. The sensor sits in the hollow column on the ambient of the tank and is affected by the magnet.
SID sends B+ to the level sensor via pin 26, and the sensor is grounded to grounding point G40/42. At normal level, the float arm is level with the switch, the magnet in the float arm closes the circuit and pin 26 of the SID is grounded. At low levels, the circuit to ground is broken.
The function generates a CHECK message in the SID (30 seconds delay).
| Diagnosis |
If there is a break in the coolant level sensor circuit “Coolant level low. Refill.” is displayed despite the coolant level being correct.
If a short-circuit to ground occurs, the CHECK message will not be shown even if the coolant level is low.
The SID will not generate a diagnostic trouble code.
