RindaTechnologies TechMate Pro - Tach Output Test; Induced Misfire Test

MerCruiser PCM-555 EFI
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Tach Output Test
e Tachometer Output test is primarily used to verify the operation of an
analog, helm mounted, tachometer. e PCM is capable of generating and sup-
plying an RPM signal to an analog tachometer. is test will command the PCM
to output a tach signal that is equivalent to 3000 rpm.
• This test should be performed with Key-On and Engine Off.
1) Review the advisory message stated above and be sure the engine is not run-
ning when attempting to perform this test.
2) Aer selecting the “Tach Output“ test from the PCM Output Test menu the
scanner will prompt you to begin the test. To initiate the test press the TEST
key. e PCM will begin sending a signal equivalent to 3000 rpm to an exter-
nally attached (usually helm mounted) tachometer gauge. e tach signal will
be active for approximately 10 seconds.
• Press and hold the NO key on the scan tool’s keypad to stop the test
at any time.
3) Aer the test is complete the scan tool will return to the Output Test menu.
Induced Misre Test
e Induced Misre Test is designed to assist a technician in nding a problem-
atic cylinder. is test commands the PCM module to disable the fuel injector on
a selected cylinder thereby causing that cylinder to misre (not produce power).
Perform the following steps to conduct the induced misre test.
• IMPORTANT: This test should be performed with the engine running at
approximately 1500 rpm, at normal operating temperature and under
moderate load.
• Do not attempt to drive the boat while performing this test.
• Follow all engine and boat manufacturer’s safety precautions and stay
clear of all moving engine components.
1) Review the warnings stated above prior to conducting this test. For best
results the engine should be running at approximately 1500 rpm and under a
moderate load.
2) Aer selecting the “Induced Misre” function from the PCM Functions menu
the scanner will begin to display one or more advisory messages. Review
these messages and be certain their instructions are followed.