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EWP warning light & buzzer Schematic

7K views 32 replies 12 participants last post by  95wagon 
#1 ·
#2 ·
lol @ 2000 hp LT1
 
#3 · (Edited)
Electric waterpump warning light - buzzer



The site is no longer available. I need this bad. I had a scare the other day because the female part of the connector that controls the relay somehow became lose and my EWP cut off and my car overheated. After having it towed home and getting no volts at the EWP connector I went to everything between it and 12volts and with the key on as soon as I touched the connector plug that separates the underhood fuse box from the relay I heard the relay click and I had 12 volts at the EWP. I determined I didn't need the connector and soldered the wires together and I'm back in business.

But I just installed the EWP 2-3 weeks or so ago and I was like "I know this ^!%$%#@ ain't dead already" lol.

But yeah I need to hook up a light. Would that go to the relay wire and set to buzz and light when the relay is closed when the ignition is on?
 
#4 · (Edited)
#5 ·
Isn't there already a "hot" icon somewhere on the cluster anyway? Seems like the factory temp gauge would indicate this condition also. There exist aftermarket gauges with programmable alert settings,as well as dedicated senders with preset alarm points if one really needs a buzzer,and/or flashing light. I've had a electric pump for over a dozen years now,and find them fairly trouble free in general. Yea,one could hook up a circuit to light up if the pump lost power. Wouldn't do you any good if it lost it's ground,or just quit working though.
 
#7 ·
I have an EWP and have been thinking about a buzzer and warning light for some time.

I have Autometer gauges that do have the ability to preset ranges, and if values move out of range an LED lights up. I have these for water and oil temp, and oil pressure.

I am in the habit of scanning the gauges while driving, but I would think an 85db buzzer and bright light would be a great addition. Cheap insurance.

Here's a post copied from another forum, which explains why I don't want to build this myself.

I'm also attaching the circuit diagram that goes with it.

How about a Gary's Innovative buzzer harness group buy! I'm in...



From the net:

Quote:
Circuit Description
This Circuit operates using an LM393 Voltage Comparitor to determine whether the current through the electric water pump has fallen below a specified threshold. The output of this comparitor (pin 1) is high whenever the + input voltage is greater than the - input voltage, and the output of the comparitor is low when the - input is greater than the + input to the device. The normal operation (No Pump Failure) of the circuit is designed so the comparitor output is high and both transistors are biased on. When the transistors are turned on the LED has current flowing through it and illuminates. The buzzer is seeing less than .3 volts with the transistors on and will not turn on.
In this circuit it is important to understand the function of the 60 milliohm (.06 ohm) resistor in the circuit. This resistor as a current sensor and can sometimes be referred to as a shunt resistor in this configuration. It is very important that the resistor is installed correctly to function properly. The resistor should be installed in the pump ground wire within a few inches of the actual ground termination lug. The sense wire to pin 3 of the comparitor needs to be installed on the pump side solder terminal of the shunt resistor so that it senses only the voltage dropped across the resistor.
When the normal operating current (5.8-6 Amps) is flowing through the shunt resistor it drops between 346-360 millivolts. This sense voltage is applied to pin 3 of the LM393. Pin 2 of the LM 393 is fixed by a voltage divider to 240 millivolts. The fixed voltage at pin 2 is the threshold for the alarm to trigger. When the sense voltage falls below 240 millivolts the comparitor output (pin 1) goes low. This action extinguishes the LED and the buzzer will sound. The comparitor threshold at pin 2 (240 millivolts) is set to trigger the alarm when pump current falls below 4 amps.
When Substituting in a 50 Milliohm Shunt Resistor
I have also substituted a 50 milliohm shunt resistor into the sensing circuit when I have not been able to find the 25 watt 60 milliohm resistors. When using a 50 milliohm shunt resistor the 5.6K ohm resistor in the voltage divider circuit should be replaced by a 6.8K ohm resistor to maintain the alarm threshold at 4 amps through the pump.
Parts List Notes
The .06 Ohm (60-milliohm) resistor in the coolant pump return will dissipate over 2 watts. A minimum power rating for this resistor should be 5 watts. But this may not be suitable for your installation as the only 5-watt resistors I found had axial leads, which seemed too small. I used a 25-watt metal case resistor that had generous soldering lugs for the 12 gage pump wires. I have found that the best resistors for this application are the metal cased wire wound power resistors.
The 390 Ohm resistor will dissipate close to ½ watt. The minimum power rating for this resistor should be 1 watt.
The remaining resistors in this circuit are ¼ watt 5% resistors.
The LED is speced to be a common red LED that drops 1.6 VDC with a nominal current of between 12-20 mA.
The Buzzer in this circuit is a piezo audio buzzer with the following specifications:
•Operating Voltage 3 - 16 VDC
•Rated Voltage 12 VDC
•Current Consumption 5.8 mA
•Resonant Frequency 4000 Hz
•Sound Pressure Level @ 10 cm Typical 86 dBA
It can be purchased online from Jameco Electronics as P/N 196357

Note: In later versions of this circuit I installed a couple of .01 µF Tantalum caps. One connected between the VCC to Ground, and the second between Pin 3 of the comparitor to ground. This should eliminate any noise from coupling into the circuit from the engine.
Thanks to Kevin Hartnett for this.

Keep in mind this setup is for the CSI/R water pump. If you run the Meziere water pump, you may have to change the values of the voltage divider due to a higher current rating of the Meziere.


DOES ANYONE HERE REALLY UNDERSTAND THIS?!!!


Gary's group buy?

Text Line Diagram Design Circuit component

Gauge Measuring instrument Tachometer Auto part Vehicle
 
#8 ·
Seems complicated...Especially,when compared to how seldom electric water-pumps fail. I suppose an electrical engineer might appreciate,and enjoy making it though. Out of the hundreds,and hundreds of these cars with electric water pumps I've not actually ever seen one with this warning system installed.
 
#9 ·
I was just about to make a post about needing the warning buzzer; I had an overheating issue today. I haven’t had time to really get into yet to find the cause. But I know I need someone who knows wiring to make this harness. I wish Gary would jump on this for us; I’d be in for a couple.
 
#10 ·
#12 ·
I dug thru my saved issf stuff from beyond the crash and dug up a couple of things I remembered from then.

first is this post, using the dash overtemp warning and a buzzer for when the engine overheats.
per the thread this applies to 96 SS's , not known how it may work for other model/years.

http://www.impalassforum.com/vBulletin/showthread.php?t=1056417

second is this diagram on a EWP warning system and buzzer.
props to whoever made it, it was from 2005 according to the pic info.


 
#14 ·
Tom Fish EWP warning setup...

I have a NOS Spartus (Tom Fish) EWP warning setup with instructions.

The only thing I'd change is the use of Posi-Loc connectors for wiring splices and taps.

I don't know if Tom would mind but I could post photos of the pieces and scans of his instructions, if appropriate.

While this may be a limited market, it seems Gary (Innovative Wiring) would be a potential manufacturer, if Tom is no longer interested. It would be tedious to assemble a kit from scratch. There is a lot of stuff involved...one of the reasons I never installed it. Monitoring the operation and maintenance of the car tends to keep me apprised of what's going on. So far the Meziere EWP is happy.

Richard Snipes
4501 Safari in Jax, FL
 
#17 ·
I know a guy who's in his last year of school to be an electrical engineer. I showed him these schematics (if that's what they're called). He understood all of it of course, and said he would show it to his prof and possibly tweak it. I'm trying to get him to make some.

It's all very preliminary, but if anything come of it I'll pass it on.
 
#19 ·
Seen many warning light/buzzer (some programmable) already on the market that seem far simpler than the diagram of this set-up. Sending unit goes into the cylinder head's coolant port. In the event the water pump stopped working,it would respond almost immediately. That being said,the car has a temp gauge,and a warning light already. Doesn't it?
 
#21 ·
I understand that...If you're waiting for someone else to make them,and offer them for sale you'll likely be waiting for a very long time. I've seen the schematic for this years ago,and have yet to actually see one installed in one of these cars. Even being familiar/comfortable with automotive electrical work. This device seems like it would be rather complicated,and time consuming to make. Maybe an electrical engineer can grasp,and put one together like that. If a warning device is that important, then it seems to me if the light/buzzer comes on immediately,or 15-30 seconds later is a pretty slim distinction.
 
#31 ·
This looks like a really simple solution. I want to research the heat resistance of the switch, and be sure if it fails it won't release parts into the coolant system.

I know they do reduce flow by a small amount, but upstream of the heater core flow restrictor I guess that wouldn't be an issue.

This is a really great idea, thanks again.
 
#24 ·
Not being negative,just realistic...These cars,and this issue have been around for a very long time...The schematics have been out there for a while too...Suppose one could figure out how to make their own if they wanted one that badly
 
#25 ·
Not debating on whether a "warning light/buzzer" is needed for EWP (although in 16+ years I don't have or find a need for one with my EWP. The dash temp gauge for me is fine). One could always wire something up or install a pillar pod mounted gauge with a "warning" light also.....if one feels the need to

one gauge with programmable warning light is

http://www.speedhut.com/gauge/GRM-WTR-01/1/Water-Temp-Gauge-50-125C-Metric-(w--warning)
 
#26 ·
GM already provides a warning 'bong'. When the IP temp gauge gets into the red, it's already too late, though.
You know how we substitute a 60psi oil pressure sender for the 80psi oil pressure IP gauge?
Can't we substitute something that would make GM's warning 'bong' go off at 239°F instead of 257°F? (At the head, for GOd's sake, not at the pump).

Disclaimer: I, for one, believe that equipping electric H2Opumps with some sort of alarm that goes off the moment it quits is a great idea - I'd still have my wagon. (Gary has since upgraded the electric H2Opump wiring harness.)
Just trying to think of a solution that'd also benefit mech H2Opump owners …
 
#28 ·
One could even install a smaller version in the "bleed-pipe" super easily...
 
#30 ·
Just entered "reed flow sensor" to a ebay/amazon search,and there's a ton of different sizes/styles available. Heck,I may even rig one up myself...
 
#32 ·
Avoid the plastic ones...Several are listed for use in boilers,they'd be okay...
 
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