5.2 Fuel treatment system – Troubleshooting
Illuminated pushbutton 'water alarm' is lit.
Cause
Corrective action
When the maximum water level
is reached, the water level
electrode opens the water drain
valve and water is discharged. If
the opening period of the valve
exceeds a preset limit
(4 minutes), the pump will
switch off and an alarm is
initiated.
1. Press illuminated pushbutton 'Water alarm' for
acknowledgment.
2. In addition to the automatic water drain function, water can
also be drained manually. To do so, press the illuminated
pushbutton 'Water drain' to open the drain valve.
Signal lamp 'Pump fault' is lit.
Cause
Corrective action
The drive motor is equipped with
an overload protection. If the
maximum permissible current
consumption is exceeded, e.g. in
case of a blockage or dry-
running, the motor protection
relay triggers and the pump is
switched off.
u
Reset motor protection relay.
Signal lamp 'Pre-alarm' is lit.
Cause
Corrective action
The differential pressure
exceeded 1.3 bar.
u
Replace coalescer filter element (→ Page 211).
Illuminated pushbutton 'Replace filter element' is lit.
Cause
Corrective action
The max. permissible differential
pressure of 1.5 bar was
exceeded. If the coalescer filter
element is not replaced,
pressure will increase further
and the safety valve will open.
Fuel will be led via the bypass
directly into the overflow tank.
1. Replace coalescer filter element (→ Page 211).
2. Press illuminated pushbutton 'Replace filter element' for
acknowledgment.
MS150035/01E 2013-11 | Troubleshooting | 101
TIM-ID: 0000007734 - 008
