Mercury 305 CID, Service Manual, Page: 708 / 967

ELECTRONIC FUEL INJECTION (MULTI-PORT AND THROTTLE BODY) - 5E-167 90-823225--1 1096
Throttle Body Injection and
Multi-Port Injection Sensor
and Module Servicing
Precautions
! WARNING
BEFORE attempting to disconnect and remove
any module or sensor, check to make sure that
the engine ignition system is OFF. Then discon-
nect the negative (–) battery cable from the termi-
nal. DO NOT reconnect the negative (–) battery
cable until the module or sensor removed has
been re-installed with secure connections.
IMPORTANT: Modules and sensors are electrical
devices easily damaged by contact with liquid
cleaners or solvents. Clean with a dry cloth un-
less specifically directed to do otherwise.
Electronic Control Module (ECM)
IMPORTANT: The ECM is a sensitive electrical de-
vice, subject to electrostatic damage. Therefore,
take care not to touch connector pins when re-
moving or installing the module.
NOTICE
Refer to “Service Precautions,” in “Repair
Procedures,” BEFORE proceeding.
REMOVAL
1. Disconnect J1 and J2 electrical connectors at en-
gine control module (ECM).
72801 b
a
d
c
Typical
a - Electrical Bracket
b - ECM
c - J1- Electrical Connector (Front Connector)
d - J2- Electrical Connector (Rear Connector)
2. Remove ECM from electrical bracket.
CLEANING AND INSPECTION
1. Clean the exterior of the ECM with a dry cloth be-
ing careful to avoid contact with connector pins.
2. Inspect outer surfaces for any obvious damage
3. Visually inspect electrical pins at both ends of
ECM for straightness and corrosion.
4. Visually inspect J1 and J2 connectors on the wir-
ing harness for corrosion and terminals that may
have backed of the harness.
NOTE: The ECM is a sealed electrical component. If
a Code 51 check has shown it to be defective, re-
place the unit with another ECM having the same part
number and service number as the original.