Bad horn relay?

[TIM R]

The horn does not work on my 2001 Echo. The fuse is good and the relay clicks when you press the horn. The new relay will be $70. Is there a way to test the old relay. Possibly a continuity test.
Thanks
Tim

[poorboywilly]

Using a ohmeter and some wire leads with alligator clips on both ends.

Remove the relay and take a look at the terminals. There should be two blades at one angle and the other two blades should be at the same angle orthogonal to the first two, like so (I've labeled the blades for reference):

1 | | 2
5 --
3 --

This is how the relays are labeled in the service manual wiring diagrams.

Step A) Check that there is continuity (there should be a bit of resistance) between 1 and 2. Check that there is no continuity between 5 and 3.

Step B) Now, using the aforementioned wire leads with alligator clips, attach a 12VDC power source (your car battery + terminal and car body ground should do nicely) to terminals 1 and 2 of the relay. Be careful with this, they are close together and it would be easy to touch the wires. You should hear the relay "do its thing". Now, check that there is continuity between terminals 3 and 5 (again being careful not to cause a short circuit).

If there was no continuity between 1 and 2 in step A or 3 and 5 in step B, or if there was continuity between 3 and 5 in step B, the relay must be replaced.