MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS
TSB Revision
MULTIPORT FUEL INJECTION (MFI) <3.0L>
13B-339
.
CIRCUIT OPERATION
•
The EGR solenoid power is supplied from the
MFI relay (terminal 4).
•
The ECM <M/T> or PCM <A/T> controls the EGR
solenoid ground by turning the power transistor in
the ECM <M/T> or PCM <A/T> "ON" and "OFF".
.
TECHNICAL DESCRIPTION
•
To judge if there is open circuit in the EGR sole-
noid drive circuit, ECM <M/T> or PCM <A/T>
measures the surge voltage of the EGR solenoid
coil.
•
The ECM <M/T> or PCM <A/T> drives the EGR
solenoid. After the solenoid is turned off, the ECM
<M/T> or PCM <A/T> will check if the solenoid
coil produces a surge voltage of 2 V or more.
.
DTC SET CONDITIONS
Check Conditions
•
Engine is being cranked.
•
Battery positive voltage is at between 10 and 16
volts.
Judgment Criteria
•
The EGR solenoid coil surge voltage (battery
positive v 2 volts) is not detected for 0.2
second.
•
The ECM <M/T> or PCM <A/T> monitors for this
condition once during the drive cycle.
Check Conditions
•
Battery positive voltage is at between 10 and 16
volts.
•
ON duty cycle of the EGR solenoid is between 10
and 90 percent.
•
ON duty cycle of the evaporative emission purge
solenoid is 0 percent.
•
Evaporative emission ventilation solenoid is OFF.
•
More than 1 second has elapsed after the above
mentioned conditions have been met.
Judgment Criteria
•
The EGR solenoid coil surge voltage (battery
positive v 2 volts) is not detected for 1
second. When the EGR solenoid is turned OFF.
.
TROUBLESHOOTING HINTS (The most likely
causes for this code to be set are: )
•
EGR solenoid failed.
•
Open or shorted EGR solenoid circuit, or loose
connector.
•
ECM failed. <M/T>
•
PCM failed. <A/T>
DIAGNOSIS
Required Special Tool:
•
MB991502: Scan Tool (MUT-II)
ACX02514
AN
EGR
SOLENOID
VALVE
CONNECTOR: B-31 <WITHOUT VARIABLE
INDUCTION SYSTEM>
AC106190AD
EGR SOLENOID
VALVE
CONNECTOR: B-31 <WITH VARIABLE
INDUCTION SYSTEM>
AK000225
CONNECTOR : C-51<M/T>, C-52<A/T>
C-52
C-51
PCM<A/T>
ECM<M/T>
AJ
AK101363AB
MFI RELAY
CONNECTOR: A-18X