The vehicle may fail to start. If the ignition switch relay is faulty, the car won't start; if the power window relay fails, the electric windows won't go up or down. Cars have multiple relays controlling various circuits, so the solution depends on the specific issue. Let's look at the symptoms of a faulty car relay.
A faulty car relay can lead to the following situations:
1. Starting circuit issues: Open circuits in the starting line, poor wire contact, or loose connections;
2. Power supply faults: Dead battery, short circuits caused by plate sulfation, or poor contact in the starter power cable;
3. Starter motor faults: Poor contact between the commutator and brushes, poor contact between the solenoid switch's contact disc and terminals, or partial short circuits in the field or armature windings.
How to replace a relay:
Vehicles contain numerous relays and fuse boxes. Typically, a car has two fuse boxes: one in the engine bay and another inside the cabin. Upon opening a fuse box, you will see various colored fuses and some black square components; these squares are the relays.
If a fuse or relay fails, the engine might not start, or certain electronic systems may stop working. Replacing them is very simple. The fuse box cover lists the corresponding functions for each component; simply locate the specific fuse or relay and replace it.
Fuses and relays are inexpensive. If your car frequently experiences fuse or relay failures, it is advisable to keep spares in the vehicle so you can replace the faulty part yourself when a problem arises.
