DESCRIPTION
SERVICE MANUAL NUMBER 22
90-860074--1 FEBRUARY 2002
Page 5A-15
Engine Control Module (ECM)
The Engine Control Module (ECM) is the control center of the fuel injection system. It
constantly monitors information from various sensors, and controls the systems that affect
engine performance.
The ECM also performs a diagnostic function check of the system. It can recognize
operational problems and store a code or codes, which identify the problem areas to aid the
technician in making repairs.
75301
D2.8L D-Tronic and D4.2L D-Tronic Engine Control Module (ECM)
The ECM is supplied voltage from the key switch through a 5 ampere fuse and holder
located in the electrical box on the port side of the engine. If the fuse is defective (blown)
certain systems will not function properly.
As an example the engine may crank but not start, since the ECM would not have a 12 volt
signal. Also, when the 5 ampere fuse is defective the scan tool will indicate “No
Communication” at the Diagnostic Connector.
75298
a
b
a -
Electrical Box
b -
5 Amp. Fuse In Holder
