Westerbeke SBEG Series Operator's Manual page 51

PROBLEM
ELECTRICAL TROUBLESHOOTING CHART
The following test procedures will require the use of a muitimeter and the
engine's wiring diagram (in this manual). Also refer to the relay testing
page. WESTERBEKE recommend's that these tests be peiformed by a
qualified technician.
TESTING INSPECTIONISOLUTION
(12 VDC is battery
+
voltage measured to ground)
Engine cranks but fails to start ... Test for B+ (12v) at terminals 30 and 86
on the K2 run relay
Check for bad connections at both terminals.
Replace the K2 relay.
II OK ...
Test for B+ (12v) at run relay K2, terminal 85 and
activate the start switch. Voltage should be less
than 5 volts.
II OK ...
Activate the start switch, test for B+(12v) at
relay K2 run relay, terminal 87.
Inspect the connections at relay K2, terminal 85,
or at the ECU connector J2, pin 19.
Replace the K2 relay.
NOTE:
For other possible causes (failure to start) such asfuel pump, speed sensor (MPU),
ignition. etc, refer to the these sections in this manual.
Engine starts, runs but shuts down ..... Test for voltage across the oil pressure sensor
terminals, with the engine running voltage should
be less than 1.0 volts.
With the PC interface, read the .....
engine shutdown fault
II OK ...
Test for voltage across the exhaust temperature
switch, when the engine shuts down, it should
read zero (0) volts.
II OK ...
The engine temperature sensor maybe faulty.
Low DC battery charge level when cranking
IIOK ...
Speed loss
II OK ...
Shorted oil pressure sensor
IIOK ...
External fault
Engines
&
Generators
39
Faulty oil pressure sensor. Replace sensor/switch.
Faulty exhaust temperature switch. Replace switch.
Loss of coolant thru exhaust elbow.
High exhaust temperature.
Test sensor, refer to component testing in this
manual.
Change battery/ Replace battery.
Check MPU and wiring. Replace MPU.
Check wiring/replace sensor
Check fire suppression system for cause