Audible Guages, calling all Electrical Guru's

Excellent,

would you be willing to establish the "good" levels with a voltmeter first?

This here is pretty much what you describe for the low voltage (oil pressure down),
Battery Low Voltage Warning w Buzzer Adjustable Lithium NiMH NiCd ion Phosphate | eBay

This appears to be adjustable for high or low, just need a piezo buzzer.

5 x DC 3 24V Black Piezo Electronic Tone Buzzer Alarm Continuous Beep DB | eBay

Don't remember from the top of my head, but is the brake fluid low going to the LED board in the center console? If so, just a relay with a buzzer will do.

A final note, apart from their original mission to alert you about whatever they are supposed to sense, especially over time, they also have a tendency to come on with an alarm although everything is in fine order.

If an alarm sounds it actually means up to 4 things:
a) the pattern actually has been rightfully sensed (i.e. oil pressure low)
b) the sensor itself failed
c) the wiring failed
d) the contacts (connectors) failed

Even though it is counter intuitive, I usually run sensing circuits with an on-off switch, so they can be turned off if identified as faulty for the rest of the trip,

cheers

braq

 

This is the one I wanted to post (instead of the piezo buzzers)

DC Digital LED Voltmeter 0 20V Limit Alarm 2 3 Wires Universal Voltage 12V 24V | eBay

You get to choose between high or low voltage alarm.

Here are the steps:

Get yourself a potentiometer (2K Ohm )

Connect + and minus to the constant resistance of the pot, wire the output (slider) to the gauge, set to "alarm" level(turn the pot toward the + side until the gauge reads what you consider the alarm level), read out voltage vs. ground.

As a result you should have values for high water temp (100C) and a voltage (i.e. 10V)

Next step is to set those voltages (i.e. the 10V high temp) with the pot and program the board, then some vibration safe install

cheers

braq

 

I know someone on my Jag forum who builds an excellent, well thought out kit for our Jags that converts the idiot temp gauge to a real gauge and includes a high temp alarm. I sent him an email to see if he is interested in putting together a kit for our cars with other alarms built in for water and such.

I will let you know what he says.
Alden

 

Ok, my tech buddy on Jaguarforums recommended this, says it will do temp and oil alarms:

Engine Watchdog TM1 " New Model" Temperature Sensor Gauge Low Coolant Alarm | eBay

Installation seems pretty simple and the price is good too:

ENGINE WATCHDOG TM2, Engine Overheating Alarm, Gauge & Sensor

Alden