BMW D7 Workshop Manual

Generator and generating equipment
Checking Procedure 1 – Impulse Transmitter
Thin red lead of impulse transmitter earths control
lamp when engine is stationery. When charge from
control unit passes through transmitter, this earth is
interrupted.
- When no or insufficient charge are shown,
control unit and/or generator are defective
- For further fault location, voltage between each
of the 2 black leads, red lead and generator
should be checked.
To check:
- Disconnect thin red lead from boat circuit and
connect 12V testlamp connected to B+ (charge
lead)
- With the engine stationary, testlamp should
light, and at 1150 rpm extinguish
- If the lamp does not extinguish, impulse
transmitter is defective and should be renewed,
or generator is not charging.
Checking Procedure 2 – Charge Current
Charge current passes from control unit (white lead)
through implulse transmitter (black lead – thick red
lead) to B+ (connection 30)
To check:
- With engine stationary, disconnect thick red
cable from boat circuit and interpose 0-40 Amp
ammeter
- Start engine, switch one or two items of
electrical equipment on (to load battery)
Checking Procedure 3 – Voltage Check
(without load)
This check enables generator to be checked
independently of control unit and battery
- With the engine stationery, disconnect control
unit from generator (2 black, red lead from 4
pole plug)
- Connect one black lead and red lead to 250V
voltmeter, ensuring remaining black lead cannot
earth
- Start engine, set to maximum speed and
compare reading with that specified (see
diagram)
- Repeat test with second lead
- If reading is correct, generator is in order and
charging fault lies with control unit or boat
circuit.
-
37