I am trying to rig up an alarm system for my electric waterpump. What i want is just a warning that the pump is dead before my car pops a head gasket. I really dont know how to go about this but i did rig up the relay for the waterpump myself so i have some experience.

heres what i was thinking...

1. hook up an indictor light that will go out when the power is cut from the pump.. not real affective b/c i probably wont see the light unless i place it eye level. but again i dont know where to splice in the light.. youd want it after a fuse so if the fuse blows the power is cut and the light goes out but the problem with that is that i didnt wire in a fuse. just a relay.

2. i was also wondering how much work it would be to hook up an audible alarm that will sound when power is cut. the problem with this is i dunno of any switch that will supply power to an alarm once the power is cut from the pump.

3. lastly i could splice an alarm into the idiot light for the check guages that will sound once that light comes on. does anyone know if theres a way to change it so the light will come one a lot sooner than redline? this idea seems like the easiest but wont really warn me that the pump has died till the car is getting hot.

any help would be greatly appreciated!

 

find out what the psi would be on that h2o pump and try to hook up something like a fuel pressure safety switch that would trigger a warning light(like a shift light,but setup for going solid when it is triggered)

i will get some more ideas but just think about it and see what you come up with

 

Have you seen this diagram from Andrew Mattei for alarm indicators for the electric water pump?

 

If the pump dies, it will probably still get power but the amps should go up and pop the fuse.
You can wire up a relay to a light.

Wire it up like this.
The relay will be powered by the waterpumps power wire.
Relay will be normally closed and will be open when there is power. Wire up a light to ignition power through the relay so when there isn't any power to the relay but the ignition is on the light will light up.

I actually talked to Meziere about a pump indicator last year and they said they were working on something but haven't heard back from them.

 

Not an electrician, but I've worked with electronics and electrical systems and am currently trying to get a degree in Electrical Engineering, so I guess I would have a little knowledge on the subject...

Sounds to me like you need a few relays. I don't know much about electric water pumps and how they are designed, what type of wiring they require, etc., but here goes.

If you are looking for something that is going to turn on when the power is cut, you would use a relay that has +12 volt active low designation, meaning that when the voltage is low to the relay from the "switch" power, the relay switches on and passes +12 V to the accessory (a light or a buzzer, whatever you want to do). Same thing applies for the idiot buzzer. You could possibly run both the light and the buzzer on the same relay as long as you wire the buzzer and light in parallel to the relay in the circuit. This will work as long as the light and buzzer don't take much current, which they shouldn't unless you are planning on wiring up a bright halogen light and an electric foghorn .

For the idiot buzzer for check engine light, you could tap into the check engine light wire (not sure where or what color the wire is) and use a +12 volt active high relay, so that when power goes to the light (light goes on), then the relay will switch on and the buzzer will sound.

The buzzer for the high temp is a little more complicated. I don't know what the voltage ranges are for the temperature gauge, so I can't really begin to suggest how to do that one.

Hope that help you a little.

 

I have a CSI Digital Temp gauge/controller in my car that can control a relay at 2 different temperatures. You can set it to turn on a buzzer or light when the temp hits for example 225.
That gauge was $79 and came with a sender and a relay and wiring,

 

thanks a lot guys.. i will try the relay and buzzer trick! thats exactly what i was looking for. Andrews LED lights are OK but they are so hard to notice if you arent looking right at them.

 

ok one question for you since you mentioned the fuse. i dont think i actually have a fuse on the relay. what i am thinking is this will only work with an inline fuse that will pop and cut power to the pump.. is that what youre saying?

found the writeup i used for the pump... Here it is.

 

So, just modify it to make the warning indicators you want. No biggie.

 

You're supposed to use a fuse, the Meziere comes with an inline one on the body side of the pigtail they supply. Running without a fuse voids the warranty.

It doesn't have to be a fuse, it can be a circuit breaker, but it has to be 20amps, no more.

 

That warning light is great and all, but what happens when the pump seizes and power is still supplied to it? or when the ground wire breaks/melts in half?

 

man i dunno jack about this stuff. so in that picture supplied would the 86 on the relay from the AC/cruise fuse not act as a fuse for the waterpump?

so whats the purpose for the relay anyway? couldnt you simply hook up the power to the red (+) battery junction and put an inline fuse in there?

 

I went through this a few months ago and in the end I decided to keep the mechanical pump. I was going to use Andrew's warning lights, but I was afraid they didn't cover all the necessary situations. One light indicated BAD GROUND, and another indicates BLOWN FUSE. But what happens when the pump burns out? Does it always draw more current and blow the fuse, tripping the indicator? Or does it form an OPEN CIRCUIT (or just really high resistance) which wouldn't turn on either indicator? Mainly, I don't know what happens to the pump when it "burns out".

Zephyr's CSI Digital Temp gauge/controller sounds like the way to go.

 

well i think the way the relay works is if the power is cut from the pump either if the pump draws too much current and pops the fuse or if it just dies and creates an open circuit... it will open that switch and close the other to power a buzzer or light.

the problem with a temp sensor buzzer is that i could have caught the problem a lot sooner had there been an alarm to catch the open circuit to the pump indicating a bad pump. unless this happens while in driving in heavy traffic with no way of pulling over, i should be able to catch the problem before the car even warms up.

 

Pump siezes, the amps should go up and the fuse blows and the light comes on.
Ground wire breaks and the light comes on.

Anytime the relay loses power, it will close the circuit and allow power to the light since the light uses a different power and ground from than the pump and relay.