Car relay and continuity

[allanw]

I don't understand why terminals 1-3 are connected. From the schematic, I'd think only 2-4 was connected initially. Then when voltage is applied across 3-5, then 1-2 is connected. Am I missing something here?

[MrPlacid]

I don't understand why terminals 1-3 are connected. From the schematic, I'd think only 2-4 was connected initially. Then when voltage is applied across 3-5, then 1-2 is connected. Am I missing something here?

I am quite sure you're right. Maybe it's bad datasheet you got there. If you have the same relay, pull it out and check it. If your right, it'll make you feel very good.

[allanw]

Yep, testing my relay, putting 12V across 3-5 makes a click, and switches continuity from 2-4 to 2-1.The trouble is, I'm trying to figure out what's wrong with my car and having this service manual have wrong instructions like this isn't helping...

[MrPlacid]

shafri,  I think this is what happen. #3 and #5 form a complete circuit when it is switched on, but it never connect to #1, #2, or #4 inside the relay.

PS: I think allan's relay is working fine and isn't the culprit.

[allanw]

Yeah the documentation is wrong. The relay appears to be fine, so something else is broken (ac/fan stopped working on my car)

[allanw]

Luckily I do have a full service manual. It says to check this heater relay for fan failure, so I tried that. I believe something must be wrong with the whole a/c power system, because the a/c light won't even turn on. I'll check the fuse next.