BMW 5 Series E39

since 1996-2001 release

Repair and operation of the car

Check of the relay

Many electric chains incorporate the relay. If the consumer joins manually, relay receives the order to bring food to the consumer. It is possible to bring food to the consumer directly from the rechargeable battery. At the considerable consumed currents the chain turns on the relay not to overload the switch. Along with the relay of inclusion there are also functional relays, for example the windshield cleaner washer relay.

Check of the relay of inclusion

At inclusion of the corresponding consumer the signal on the relay is given. At the same time electric current of management, influencing the electromagnetic coil, closes a contour of working current, providing the consumer's food.

It is the simplest to check operability of the relay, having replaced it with another, serviceable. So for example, arrive on HUNDRED. In the absence of the spare relay it is recommended to make check as follows. The designations of plugs given below can differ from available.

CHECK

1. Take out the relay from the holder.
2. Include ignition and the corresponding switch.
3. By means of the device for control of tension check whether there is tension on the plug 30 (+) holder of the relay. For this purpose attach the device to weight(s), and carefully enter other tip of the device into the plug 30. If the light-emitting diode of the device lights up, tension is. If the device shows lack of tension, check according to the scheme whether there is no break on the way from a positive pole (+) rechargeable battery to the plug 30.
4. Prepare a crossing point from the isolated wire with the smoothed-out ends.
5. Connect a crossing point the plug 30 in the holder of the relay (+ rechargeable battery, always gives tension) to an exit of the closing contact of the relay (plug 37). Thereby operation of the serviceable relay is imitated. Where there are plugs in the holder of the relay, it is specified the relay.
6. If at the included crossing point the consumer works, it is possible to draw a conclusion on malfunction of the relay.
7. If the consumer does not work, find out, whether as it should be connection of weight to the consumer. Then check connection from the plug 87 to the consumer. At break eliminate malfunction.
8. If it is necessary, insert the new relay.

If malfunction appears periodically, then, as a rule, relay is the reason. In this case adhesion of contacts can take place. In this case slightly strike with a finger the relay case. If the relay at the same time works, replace it.