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All of the appropriate electrical parts are provided with your Water Watch.

Unplug sensor from wiring harness before turning

Fitting instructions for specific vehicles are supplied with our Mounting bracket kits which are available to suit many different vehicles - a comprehensive list is available with many new bracket kits being developed. If a bracket kit for your vehicle is not listed - please contact us for assistance.

Water Watch Water in Diesel Fuel Alarm

Step by Step Instructions

1. If you have not purchased a bracket kit, depending on the vehicle that you have and where you want to mount the unit you may need to purchase extra fuel line, clamps, fittings, alloy angle or steel and necessary cable ties and fastenings to mount the components.

2. Find a suitable place for the unit, as close to the original fuel filter as possible and between it and the fuel tank in an upright vertical position. (Do not remove the vehicles genuine fuel filter assembly).

3. Now that you know where the unit is to be placed, if you have not purchased one of our brackets, make a bracket out of the alloy angle or steel ensuring that it is rust proofed.

4. Connect the fuel lines to the filter ensuring that the arrows on the unit are pointing in the direction of flow. The arrow can be seen between the bolts in the picture to the left.

5. Mount the relay close to the water trap ensuring it is positioned vertically with the electrical pins facing down (keeps water out). If drilling, ensure there are no wires in the path of the drill.

6. Mount the supplied LED Lamp to a visible place on your dash board. Remove nut and washer behind LED - slide sticker onto back of LED and mount on dash securing with washer and nut.

7. Mount the supplied buzzer behind/under your vehicles dashboard - the alarm sound is louder when the buzzer faces into the cab. The buzzer sound can be dampened by using elecrical tape if necessary.

8. Locate positive battery voltage from the ignition switch 'ON' position. To find the correct live wire use a test light or multimeter and ensure it is ignition positive by ensuring it is live only when the ignition is on.

Water Watch Water in Diesel Fuel Alarm
Water Watch Water in Diesel Fuel Alarm
Water Watch Water in Diesel Fuel Alarm
Water Watch Water in Diesel Fuel Alarm
Water Watch Water in Diesel Fuel Alarm
Water Watch Water in Diesel Fuel Alarm

9. Disconnect all batteries in the vehicle.

If unsure, seek assistance from a licenced auto electrician.

10. Connect one White wire from either the relay end or alternatively the opposite (under dash) end of the wiring harness. If this wire is not from a fused source, fit the fuse holder and 5 amp fuse supplied

(see wiring diagram)

Run the wires through into the cabin area of the vehicle, find a rubber grommet in the firewall to run the wires through (you can use a lubricated coat hanger to do this), be careful not to cut the grommet as this will compromise waterproofing.

11. Connect the Black wire with eye terminal at the relay end to veichle earth

12. Connect the Red wire from both the LED light and buzzer to the white wire at the under dash end of the wiring harness.

LED light and buzzer wiring connections should hae soldered joints.

Using flexible conduit, cable ties and electrical tape tidy up wiring ensuring it is clear of moving parts such as the steering column or areas of extreme temperature like the exhaust. It is often a good idea to try follow the route of wires already in the engine bay.

Check your work. Check that wire connections are all connected and secure and that all fuel lines are in the correct order and tight.

Reconnect all the batteries and turn on the ignition, the unit should self-test (for a period of 3 seconds) this is normal operation.

Start the engine and check the fuel lines for any signs of moisture, if there are turn off the engine and tighten before checking again.

It may be necessary to bleed your system in order to start the engine, please refer to your vehicle handbook.

Water Watch Water in Diesel Fuel Alarm
Water Watch Water in Diesel Fuel Alarm
Water Watch Water in Diesel Fuel Alarm

Place warning sticker on windscreen, on the off chance that the alarm triggers and you are not driving the vehicle, place the instructions in the glove box for quick reference.

You Tube Fitting Video

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