A defective thermal switch makes it difficult to start the engine.
Withdrawal
Disconnect the thermal switch connector.
Unscrew the thermal switch.
On the hexagon of the switch, engraving indicates the duration of switching on (in the figure: 12 seconds at 20°C). Only thermal switches with an on-time of 8 seconds at 35°C are installed.
Warm up the thermostatic switch to the appropriate temperature by placing it in a water bath.
Measure resistance at 30°C. Setpoints:
- between terminal -G- and ground (corps): 25-40 ohm;
- between terminal -W- and ground: 0 Ohm (short circuit);
- between terminals -G- and -W-: 25-40 Ohm.
Measure resistance at 40°C. Setpoints:
- between terminal -G- and ground (corps): 50-80 ohm;
- between terminal -W- and ground: 100-200 Ohm;
- between terminals -G- and -W-: 50-80 Ohm.
In the event of deviations from the specified values, replace the thermal switch.
Installation
Screw in the thermal switch.
Check coolant level, top up if necessary.
Remove air from the cooling system.