Monaco SIGNATURE 2001 series, Owner'S Manual

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The Centroid fuel sender has no moving parts. It works by measuring
capacitance, an electrical property, between its inner and outer tubes in the
tank. The more fuel between the tubes, the higher the reading. Electronics in
the hockey-puck head of the sender convert the capacitance to current to
drive the fuel gauge.
Connections:
The Centroid sender has four connections:
• Positive and Negative: Battery voltage to run the
electronics in the sender head.
• Send: Connects to the Send terminal of the gauge
on the dash.
• Alarm: Makes a connection internally to the Negative terminal
when the low alarm fuel level is reached (when gauge is reading
about 1/8 tank). This turns on the alarm light on the dash. It is not
adjustable.
Adjustments:
The Centroid sender has two adjustments:
Empty
: Adjusts for length of sender. It has been set at the factory and
covered with a sealant. It should not be changed.
Full Adjustment : The full adjustment can be used to correct for slight
differences between fuel meters. During installation, it has been calibrated
for your meter and should not need readjustment.
The correct adjustment technique, with a full tank of fuel, is to start
with the full adjustment screw completely clockwise. This should cause the
reading to be above full. Adjust slowly counterclockwise until the full mark
is reached.The intent is to always adjust downscale rather than upscale.
Troubleshooting:
A. Electronic output. The sender has a transistorized output. This prevents
an ohmmeter from getting a correct reading of its output resistance.
B. Fuel Only: The sender will not work correctly in conducting fluids such
as water (it will read above full all the time in water). One possibility,
when you have a constant above-full reading, is that you have water at
the bottom of the fuel tank.
C. Contact Centroid: Probably 90% of the returns Centroid tests work okay
on the bench. If you have incorrect readings contact Centroid (telephone:
800-423-3574, or (preferable) fax: 904-423-3709) with your symptoms.
You will be provided with a short “fill in the blanks” troubleshooting test
appropriate to your sender. It is easier to find the problem that way than
after the sender has been removed from the system, since the problem is
not necessarily with the sender.
Chassis Information
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S I G N A T U R E 1 0 • 2 9 8
FUEL SENDING
UNIT
Fuel Sending Unit.