Attention! The RDC system cannot warn of sudden and severe tire damage, rupture due to external factors.
Tire pressure monitoring system (RDC) or tire damage system (RPA) monitors the pressure in all four wheels while the car is moving. When the pressure in one or more tires drops, the indicator on the instrument panel lights up, which informs that the pressure in the tire (Oh) drops noticeably. Pressure standards (1 bar = 1 kgf/cm2) air in tires are given in the plate attached to the end of the driver's door (pic. 1.58) and are specified at normal tire temperatures. recommended by BMW.
When driving with a trailer, it is necessary to focus on the figures given for the maximum loaded vehicle.
When checking tire pressure, do not forget about the spare or compact tire, the pressure in it should be 4.2 bar. Checking the tire pressure should be carried out some time after its adjustment in order to allow the processes in the injected air to proceed.
Attention! Tire pressure should be checked regularly, at least twice a month, and every time before a long trip.
When installing tires of other sizes and brands, the pressure may not correspond to the table value. The compact wheel does not have an RDC sensor.
Incorrect tire pressure adversely affects vehicle handling and increases the risk of tire damage. shortens their service life and may cause an accident. In order for the RDC system to remember the correct pressure values, it is necessary to check the air pressure in the tires of all wheels on the instrument (pressure gauge) and compare them with table values and correct it if necessary. Now you can enable the RDC system. Turning on the RDC system must be carried out in the following order:
- check and correct tire pressure;
- turn the ignition key to position «2», start the engine, but do not move from a place;
- press the key (pic. 1.59) and keep it pressed until the system indicator on the instrument panel lights up yellow for a few seconds;
- start moving.
Release the key. A few minutes after the start of the movement, the RDC system will remember the tire pressure readings and take it as a program value.
If the tire pressure has been adjusted, then it is necessary to repeat the procedure for memorizing it by the RDC system, otherwise the system turns on automatically when the ignition key is set to «2» and the system in the process of movement is always in working order.
If the pressure in one or more tires drops, the yellow indicator on the instrument panel lights up and the message appears on the display of the automatic diagnosis system «Check Tyre Pressure» («Check tire pressure»).
Sometimes the requirement to check the pressure appears soon after it has been corrected. This means that the tires were over-inflated or under-inflated when the tire pressure was corrected. It is necessary to check the pressure again, bring it to normal and turn on the RDC system again.
When a tire is damaged (abrupt release of pressure), the yellow indicator on the instrument panel lights up, the message «Tyre Defect» («Tire damage») and a beep sounds.
Under such circumstances it is necessary:
- take your foot off the gas pedal;
- if traffic conditions permit, do not use the brake pedal or use it with extreme caution;
- direct the car, avoiding sudden movements of the steering wheel;
- slow down until the car comes to a complete stop;
- replace the damaged wheel.
It is important to remember that the RDC system may experience interference from other systems and devices operating on its frequency. During interference, the yellow indicator on the instrument panel lights up and the message appears on the display of the automatic diagnostic system - «Tyre Control Inactive» («No tire pressure monitoring»). Similar information comes:
- in case of malfunctions in the system;
- if one of the wheels does not have an RDC system unit;
- if there are other wheels with an RDC system unit in the car, not counting the spare wheel;
- after application on wheels of non-standard blocks of the RDC system (exchange of information on a different frequency). Memorization of new identification numbers lasts several minutes, only after that the system is able to respond to a drop in tire pressure and notify about it.