Car Thermostat has 3 diff coloured sensors (green,blue & bro

[Jennysbest]

For the Peugeot 406 SALOON 2000, petrol.

The thermostat housing has 3 different coloured sensors coming in to it, green, blue, and brown.

What are each of these, and their job ??

One is the engine temperature sensor,
which shows you the on the dashboard, the temperature of the engine

Here are pictures.






What does the green one do?

What does the blue one do?

What does the brown one do?

Thank you.

[8Jb9]

They are all coolant temperature sensors for cars that are "pre-mux", that is to say before the cars were fully multiplexed. For the V6 that change came with the ES9J4S-engine, it only has the green sensor. Mine, on the other hand, a 1999 ES9J4, has all three. For the V6 the following colour code is valid:

- Green: temperature info for the engine control unit
- Blue: temperature info for the gauges in the dash
- Brown: overtemp warning / fan control