How To Wire A 3 Prong Flasher Relay?

1. First of all, the most important thing to start with is to identify which terminal relates to which item. The generic flasher relay usually have a 'B' which stands for battery, 'L' which stands for load terminal and 'P' which usually stands for the panel or dash indicator terminal. If you need help with this then the circuit is usually illustrated on a label diagram usually located on the casing of the relay. If they are not labeled, use an ohmmeter to determine which prong is open at rest, i.e., has infinite resistance across to either of the others. This is the 'P' terminal. The other two are interchangeable.
   
   
2. With the long stripped end of the wire, wrap it around the base cylinder of the test bulb securing it with a twist, and connect the short-stripped end to the 'L' prong using the third clip.
   
   
3. Next, clip the test light lead between the 'P' terminal and the negative terminal of the battery. Connect the 'B' terminal to the positive terminal of the battery using the test wire with equal-length stripped ends, with one clip on each end.
   
   
4. Place the center connector of the test bulb on the battery, the unit should now start flashing thus causing both test bulbs and the load bulb to blink. If the bulb and the test light blink at regular intervals, the relay is functioning properly. Otherwise, the unit needs a replacement.
   

Once you have made sure all parts are working you can now connect the wires up to the actual instrument in question. If in doubt refer to the handbook or the manufacturer for advice.