MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS
TSB Revision
MULTIPORT FUEL INJECTION (MFI) <3.0L>
13B-541
.
CIRCUIT OPERATION
•
The service engine soon/malfunction indicator
lamp power is supplied from the ignition switch.
•
The ECM <M/T> or PCM <A/T> controls the
ground of the service engine soon/malfunction
indicator lamp by turning the power transistor in
the ECM <M/T> or PCM <A/T> ON and OFF.
.
COMMENT
•
In cases such as the above, the cause is proba-
bly that the ECM <M/T> or PCM <A/T> is detect-
ing a problem in a sensor or actuator, or that one
of the malfunctions listed at right has probably
occurred.
.
TROUBLESHOOTING HINTS (The most likely
causes for this case:)
•
Short-circuit between the service engine soon/
malfunction indicator lamp and ECM <M/T> or
PCM <A/T>.
•
Malfunction of the ECM <M/T> or PCM <A/T>.
DIAGNOSIS
Required Special Tool:
•
MB991502: Scan Tool (MUT-II)
AK000312AI
CONNECTOR:C-41
AK101421AD
CONNECTOR: C-111
AK101420AD
CONNECTOR: C-108
AK000733AC
CONNECTOR:C-28
AK000225
CONNECTOR : C-51<M/T>, C-52<A/T>
C-52
C-51
PCM<A/T>
ECM<M/T>
AJ
AK000219
CONNECTOR:C-87
AC