Left: In the top left hose fitting at the cylinder head of the 5-cylinder model, there is an electronic thermal switch. The contact arrangement is as follows:
T — temperature indicator;
R — air conditioner;
+ — food;
C — "coolant overheating" indicator light.
Right: Models with a 6-cylinder engine have the same electronic thermal switch (arrow) with an identical contact arrangement. It is screwed into the coolant pipe, at the rear right of the engine.
On the back of the instrument cluster, a voltage stabilizer (arrow) is installed on the side of a small radiator.
To remove them, you must first remove the instrument cluster (see beginning of chapter). Then unscrew the main panel from the back. Checking the instruments:
Oil pressure sensor, oil temperature sensor: disconnect the wire from the corresponding sensor (installation position, see next section) and bring to "mass":
If the instrument's arrow does not move, then either the wiring or the instrument itself is faulty.
Otherwise, the cause of the malfunction is the sensor.
To remove individual devices, unscrew the cover from below, release the central fastening nut, and remove the device.
Clock: check the voltage at the clock contacts with a voltmeter.
Power is present, but there is no indication: the watch is faulty.
Installation position of oil pressure sensor, oil temperature sensor
4-cylinder models: Both sensors are located on the oil filter flange on the left side of the engine.
Models with 5-cylinder engine: the pressure sensor is located on the left side of the engine block, the oil temperature sensor is on the right front at the bottom of the engine. It is screwed in there instead of the threaded plug for the oil pump relief valve. The plug is under spring tension. The position of the spring and the valve plungers is extremely important!
Models with 6-cylinder engine: The oil pressure sensor is located in cars produced before 7/91, at the rear of the left cylinder head, and from 8/91 on the left side of the engine block at the front below. The oil temperature sensor is located at the left bottom on the end side of the engine. The wires to the sensors are assembled in a plug-in connection at the rear of the left cylinder head. The colors of the cables in the plug-in connection are: green-black or black-brown to the oil temperature sensor; blue-white or black-white to the oil pressure sensor; white-gray for hydraulic switch 1.8 or 2.5 bar; blue-black to the switch with hydraulic drive 0.3 bar.
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