so, the F1 relay, I need to ask a question

Any reason not to upgrade to the Scud Ing Swiss relay? It has monitoring lights integrated into it. It's a definite upgrade and it's plug and play.

 

assuming its a bosch relay, google the model and see if it brings up a schematic.
Otherwise get a battery charger Wires and connect to a pair until it clicks, that is the coil. The other pair are the inlet supply and out to the load

 

You stick one end of the bulb to the line that energizes with the pump. Then the other end of the bulb to chassis ground. You don't want to put it across the coil.

If using a LED make sure you use a resistor in series.

 

Without a resistor you will get only one blink out of the LED.

 

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This diagram shows pins 8 and 2 carrying the power to the pump (when the relay coil is powered). That corresponds to the 4 and 1 in your photo.

 

Just wedge two small gauge wires into sockets 8 and 2 when you reinstall the relay. Attach the lamp to the ends of the wires.

NB: the grey wire going to the relay is hot battery power. Don't short it to anything.

 

You want to connect LED+ to pin 8 and then LED- to chassis ground through a resistor. You don't want to try and bridge the relay with a bulb since it will act like a wire and try to power the pump and just burn out.

 

In order for you to attach bulbs to the relay you will have to tap into F1 relay power wires.
That means you will have to cut & splice wires, or solder wires for solid connection. Never use tap splices as those are pure crap.
Ask me how I know.

You can try and wedge wires into the relay sockets but those contacts are really tight so i dont think that will work.

The best solution as mentioned is Scud Ing Swiss F1 solid state relay.
If you need to get a hold of him let me know as I have his eMail address and I can contact him to reach out to you.

Dan

 

Sorry, correction ... Sj_engr is correct. That is, put one wire on pin 8 (the red/black wire) and one wire to earth with the lamp attached to the wires. But as previously mentioned, this is not proving that power is getting to the pump, just that power is going through the relay as required.

 

What about using diagnostics to data log 'pump on'?

 

Only if you're using an LED do you need a resistor. I've seen 550 ohms in series with LEDs in Ferrari switches, so this is probably a good starting point. You may see your local electronics hobby shop use the expression "550R" instead of using the ohms (omega) symbol.

 

I think the issue with that approach is that it will only display pump COMMANDED on. It won't show if the relay has become stuck, etc.

Sent from my SM-A515W using Tapatalk

 

My take on this: the relay is a cheap part (£5 or something from Eurospares). I keep one new one behind the trim panel in case of emergencies. I keep a diagnostics tablet in the car to check anything else like system pressure. The relay is cheap enough to be a service part every five years or so.

If there's an issue at the side of the road I can figure it out with diagnostics or swapping the relay.

If there's an issue at home I have a multimeter and more tools to hand.

 

You should be able to solder a thin wire to the top area (closest to the relay body) of the Relay post. Any 200-500 ohm value should be fine and actually depends on the color of your LED. You need high activation voltage for blue but I am sure you can find specifics on a webpage.

 

I understand, but I would have thought that logging system pressure & pump on request, and then overlaying the data will give you exactly that.