Circuit description
A
sensor
is located in the water trap under the fuel filter.
Its task is to detect whether there is water in the fuel.
The EMS 2 senses the voltage drop between the pins
B10 and B8. The pins are in contact with the fuel. When
there is no water in the fuel, the voltage is 0,8 x battery
voltage. If there is any water in the fuel, voltage will
drop.
The sensor is connected via pin B10 on the engine
control unit to battery negative.
Measurements
Checking supply cable, water in fuel
switch page 145
Checking negative cable, water in fuel
switch page 146
Checking water in fuel switch page 146
10
8
2
3
SB
Y
A
B
EMS2
p0013479
A Connector B
B Water in fuel
30-2 Fault Tracing
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