Big Clive's idiot brother - relay help

[The Moog]

The intermittent wiper relay on the k11 Micra is being a pain. The one I could find on eBay is £40 which feels a bit expensive for me.

 

After watching too much Big Clive, I now think I have much more electrical capabilities than I did last week.

 

I understand the normal kind of relays, but this bad boy has 6 connectors.

 

Can anyone explain to me how this works? What can I test to see where the issue is?

 

Pics are a bit shit, but I can get better if that would help

[Three Speed]

If you can see the terminal numbers (which are probably printed on the bottom or the relay so may not be visible unless you unsolder it from the board. If it's knackered you'll have do that anyway):

Terminals 1 and 2 are the coil. So if you connect 12V across them it should make the relay switch. Try it both ways round polarity-wise. There would be a small click if the relay moves.

Terminal 4 - there may be several of these - they are all connected together - is one side of the load that the relay is switching. 

Terminal 3 is the switched side. There may be a Terminal 5 - if its there this is a changeover relay, if not it's just a simple single throw job.

If you can make the relay switch using 12V, measure the resistance across 4 and 3 - it should change between open circuit and closed circuit as you switch the relay. 

The relay is available from electrical component suppliers for about a  fiver but you'll have to unsolder the thing from the board and then resolder all the connections. Unsoldering something like this is a lot easier if you have a solder sucker otherwise it's difficult to get all the legs to stay unsoldered at the same time.

[The Moog]

Cool excellent help . Will have a look at solder suckers.

I think the relay also does the wiper park as when I unplugged it, that stopped working.

Would that be right?

[Three Speed]

I can imagine it might - but I don't know.

[Fumbler]

I believe it does that yes.

[hairymel]

Is the little 8 pin chip on the back of the board assploded ?

Looks like it might be damaged in your pic

[The Moog]

Is the little 8 pin chip on the back of the board assploded ?
Looks like it might be damaged in your pic

Will pull out the relay tomorrow and have a closer look.

[somewhatfoolish]

7 hours ago, hairymel said:

Is the little 8 pin chip on the back of the board assploded ?

Looks like it might be damaged in your pic

Maybe, might just be a blob of flux or lacquer though.

[Richard]

It looks like the conformal coating to me.

I'd probably start by replacing the two electrolytic capacitors, they are the only components that would degrade. Actually I'd start by reflowing the solder on all the plug pins, if that didn't work I'd move onto the capacitors.