Bosch Appliances MMD 540H instruction manual To measure pulse width mS, Connect

24 MMD 540H Hybrid Multimeter Meter Functions

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To measure pulse width (mS):

ÑSelect the “mS-Pulse” function with the rotary switch .

ÑPress 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:

Ñ Black lead in COM jack.

Ñ Red lead in V-Ω-RPMjack.
Connect:	Black–	Red+
Jumper wires between the
fuel injector and the harness		Good Ground
connector.	Mixture
		Jumper Leads From
	Control
Black test probe to a good		Port Fuel Injector
	Shown

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.

Robert Bosch LLC MMD 540H Instruction Manual Version 1 February 2008