Robert Bosch LLC
MMD 540H Instruction Manual | Version 1 | December 2010
MMD 540H Instruction Manual | Version 1 | December 2010
Robert Bosch LLC
(continued from previous page)
To measure pulse width (mS):
f
Select the “
mS-Pulse
”
function with the rotary
switch .
f
Press the
±TRIG
button for
2 seconds until the negative
(-) trigger slope is displayed
on the upper left side of the
display.
NOTE: The applied time for
most fuel injectors is displayed
on the negative (-) slope.
Insert:
f
Black lead in
COM
jack.
f
Red lead in
V-Ω-RPM
jack.
Connect:
Jumper wires between the
fuel injector and the harness
connector.
Black test probe to a good
ground at the fuel injector or the negative (-) vehicle battery post.
Red test probe to the fuel injector solenoid driver input on the
jumper cable.
Start the engine. A pulse width in milliseconds should be read.
NOTE: Initially, the unit will read “OL”, then readings will descend
and stabilize to the actual pulse width. If “OL” remains, re-check
your connections.
Meter Functions – RPM/×10RPM
f
Select the
RPM
range with the rotary
switch.
OR
f
Select the
×10RPM
range with the rotary
switch (1,000 to 12,000 RPM). Multiply
the displayed reading by ten to get
actual RPM.
Press
STROKE
/
DIS
button to select
through
RPM
for 4-stroke,
RPM
for
2-stroke and
DIS
ignitions.
Insert the inductive pickup connecting
terminals into the meter.
f
Black lead in
COM
terminal.
f
Red lead in
V-Ω-RPM
terminal.
Connect the inductive pickup to a spark
plug wire. If no reading is received, unhook
the clamp, turn it over and connect again.
NOTE:
f
Position the inductive pick-up as far away from the distributor
and the exhaust manifold as possible.
f
Position the inductive pick-up to within six inches of the spark
plug or move it to another plug wire if no reading or an erratic
reading is received.
RPM 4:
For RPM of 4-stroke engines which have 1 ignition on every
4 engine strokes
RPM 2:
For RPM of DIS ( Distributorless lgnition System) & 2-stroke
engines which Have 1 ignition on every 2 engine strokes
NOTE: The rpm pick-up has an adjustable sensitivity switch that
can also be used to correct an unstable reading.
24
| MMD 540H Hybrid Multimeter |
Meter Functions
MMD 540H Hybrid Multimeter |
Meter Functions | 25
Black–
Red+
Good Ground
Jumper Leads From
Port Fuel Injector
Mixture
Control
Shown
