Check of work and replacement of the sensor of a measuring instrument of temperature of a cooler. BMW the 5th E28/E34 series (from 1981 to 1993 of release)
Repair of BMW E28 and series E34 from 1981 to 1993
1. Cars of the BMW brand of 5-series
2. Engine
3. Cooling system
3.1. General information
3.2. General information on antifreeze
3.3. Check of work and thermostat replacement
3.4. Removal and radiator installation
3.5. Work check, removal and installation of the fan of cooling of the engine and coupling of its drive
3.6. Check of operation of the water pump
3.7. Removal and installation of the water pump
3.8. Check of work and replacement of the sensor of a measuring instrument of temperature of a cooler
3.9. Diagnostics of malfunctions of system of cooling
4. Power supply system
5. Ignition system
6. Control systems of the engine and decrease in toxicity of the fulfilled gases
7. System of production of the fulfilled gases
8. Coupling
9. Manual box of gear shifting (RKPP) and automatic transmission (AT)
10. Transmission line
11. Steering and suspension bracket
12. Brake system
13. Body
14. Control body sizes
15. Heater and air conditioner
16. System of onboard electric equipment
17. Routine maintenance of the car
18. Size table and adjusting data
19. Schematic electric circuits
20. Governing bodies and operation receptions
21. System of onboard diagnostics - a principle of functioning and codes of malfunctions


3.8. Check of work and replacement of the sensor of a measuring instrument of temperature of a cooler

Before the work beginning the engine should cool down completely.

The system of indication of temperature of a cooler consists of the measuring instrument of the temperature which has been built in in an instrument guard, and the block of the sensor of temperature of the cooler which has been usually located on a casing of the thermostat (see an illustration). On some cars it is established more than one sensor, but only one of them is used by a temperature measuring instrument. On M40 engines the block of the sensor is established on the left back side of a head of cylinders.

If there are suspicions that the measuring instrument works incorrectly, first of all check cooler level in system. Make sure that conducting between the sensor and a measuring instrument is not damaged, and that safety locks as it should be. (If you suspect that is faulty as well a measuring instrument of level of fuel, a problem almost for certain in an instrument guard or its conducting).

Before check of an electric chain cope with the corresponding schematic diagrams (see. Head System of onboard electric equipment). If the sensor block simply earths a chain, make check, having earthed a wire connected to the sensor, at the included ignition (but without starting the engine, with a view of safety). If the measuring instrument thus reads off scale, replace the sensor block. If the measuring instrument does not react, or it, or its conducting are faulty. Where the block of the sensor has two plugs, check a chain, having measured resistance of the block. During writing of this Management there were no exact figures, but normal resistance should make approximately from several hundred to several thousand Ohm (depending on temperature). The indications equal to zero (at short circuit) or infinity (at the opened chain) will indicate the faulty block of the sensor.

Do not earth a wire more, than on pair of seconds, differently it is possible to damage a measuring instrument.

If it is necessary to establish the new block of the sensor, at first let's to the engine cool down completely. At removal of the sensor a little cooler therefore or be going to bring together him will flow out, or keep the new block in readiness to establish it right after removal old. Disconnect conducting, then give screws and remove the old block of the sensor from the engine then establish the new. Put hermetic on carvings. Connect conducting and in end check cooler level.

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3.9. Diagnostics of malfunctions of system of cooling