Electronic Control Module (Ecm); Ecm Removal And Installation - Mercury 25 EFI Service Manual

Ignition

Electronic Control Module (ECM)

This electronic control module (ECM) is an alternator driven component. It does not require a 12 volt battery source to function.
As the flywheel is rotated by the recoil rope or with the electric starter, the ignition stator generates voltage to energize the
ECM, ignition coils, and the high pressure fuel pump. The ECM receives information from the CPS, engine temperature sensor,
manifold pressure sensor, oil pressure sensor, air temperature sensor, and calculates the engine rotation position, engine
RPM, ignition timing, fuel injection timing, and fuel injection pulse width (duration). The ECM will also store past running
information and failure codes; and generates a warning horn and warning light during the event of over temperature, insufficient
oil pressure, or a sensor out of parameters.
Engine operating information and stored running history can be monitored and reviewed with the CDS and the harness adapter
that connect between the CDS and the ECM diagnostic port.
CDS G3 Diagnostic Tool Kit
Adapter Harness
Adapter Harness
Extension Cable

ECM Removal and Installation

ECM Removal
1. Disconnect the engine harness plug from the ECM.
2. Remove the fuse holder from the ECM.
3. Remove the two bolts securing the ECM to the mounting bracket.
b
a
ECM Installation
1. Install and secure the ECM with two bolts. Tighten the bolts to the specified torque.
2. Connect the engine harness connector to the ECM.
3. Install the fuse holder to the ECM.
b
a
Description
Bolt securing ECM
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© 2016 Mercury Marine
8M0114141
84‑899150T01
84‑822560A7
84‑825003A 1
Engine harness plug
ECM diagnostic access
Fuse holder
Bolt securing ECM (2)
Engine harness plug
ECM diagnostic access
Fuse holder
Bolt securing ECM (2)
Nm
90-8M0105568 eng MARCH 2016
lb. in. lb. ft.
6 53