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Wiring DiagramNLEC0747MODELS WITH ECM IN ENGINE COMPARTMENTNLEC0747S01
YEC730
DTC P1620 ECM RLYYD22DDTI
Wiring Diagram
EC-1256
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MODELS WITH ECM IN CABINNLEC0747S02
YEC864
DTC P1620 ECM RLYYD22DDTI
Wiring Diagram (Cont'd)
EC-1257
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Diagnostic ProcedureNLEC0748
1 CHECK ECM POWER SUPPLY CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect ECM relay. (For ECM relay location, refer to ªEngine control component parts locationº, EC-1071.)
3. Check voltage between ECM terminals 1, 6 and ground with CONSULT-II or tester.
SEF399Y
OK or NG
OK©GO TO 3.
NG©GO TO 2.
2 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors E76, F13 (where fitted)
+10A fuse
+20A fuse
+Harness for open and short between ECM relay and battery
©Repair open circuit or short to ground or short to power in harness or connectors.
3 CHECK ECM INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminals 107, 108, 109 and ECM relay terminal 7. Refer to Wiring Diagram.
Continuity should exist.
4. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 4.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
4 CHECK ECM OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 325 and ECM relay terminal 2. Refer to Wiring Diagram.
Continuity should exist.
2. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 6.
NG©GO TO 5.
DTC P1620 ECM RLYYD22DDTI
Diagnostic Procedure
EC-1258
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5 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors M11, E106 (LHD models) (where fitted)
+Harness connectors M78, E120 (RHD models) (where fitted)
+Harness connectors M71, F45 (where fitted)
+Harness for open and short between ECM relay and ECM
©Repair open circuit or short to ground or short to power in harness or connectors.
6 CHECK ECM RELAY
1. Apply 12V direct current between ECM relay terminals 1 and 2.
2. Check continuity between ECM relay terminals 3 and 5, 6 and 7.
SEF296X
OK or NG
OK©GO TO 7.
NG©Replace ECM relay.
7 CHECK INTERMITTENT INCIDENT
Refer to ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-1135.
©INSPECTION END
DTC P1620 ECM RLYYD22DDTI
Diagnostic Procedure (Cont'd)
EC-1259
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SEC220B
DescriptionNLEC0749The ECM consists of a microcomputer and connectors for signal
input and output and for power supply. The unit controls the engine.
On Board Diagnosis LogicNLEC0750
DTC Malfunction is detected when ... Check Items (Possible Cause)
P1621
0903+ECM input signal processing function is malfunc-
tioning.+ECM
(ECCS-D control module)
SEF817Y
DTC Confirmation ProcedureNLEC0751WITH CONSULT-IINLEC0751S011) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Turn ignition switch ªOFFº, wait at least 20 seconds and then
turn ªONº.
4) If DTC is detected, go to ªDiagnostic Procedureº, EC-1261.
WITHOUT CONSULT-IINLEC0751S021) Turn ignition switch ªONº and wait at least 2 seconds.
2) Turn ignition switch ªOFFº, wait at least 20 seconds and then
turn ªONº.
3) Perform ªDiagnostic Test Mode II (Self-diagnostic results)º with
ECM.
4) If DTC is detected, go to ªDiagnostic Procedureº, EC-1261.
DTC P1621 ECM 15YD22DDTI
Description
EC-1260
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Diagnostic ProcedureNLEC0752
1 INSPECTION START
With CONSULT-II
1. Turn ignition switch ªONº.
2. Select ªSELF DIAG RESULTSº mode with CONSULT-II.
3. Touch ªERASEº.
4. Perform ªDTC Confirmation Procedureº, EC-1260, again.
5. Is the DTC P1621 displayed again?
Without CONSULT-II
1. Turn ignition switch ªONº.
2. Erase the Diagnostic Test Mode II (Self-diagnostic results) memory.
3. Perform ªDTC Confirmation Procedureº, EC-1260, again.
4. Perform ªDiagnostic Test Mode II (Self-diagnostic results)º.
5. Is the DTC 0903 displayed again?
YesorNo
Ye s©Replace ECM.
No©INSPECTION END
DTC P1621 ECM 15YD22DDTI
Diagnostic Procedure
EC-1261
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On Boar dDiagnosi sLogic
DTC Malfunctionis detecte dwhe n... CheckItem s(Possibl eCause)
Wit hCONSU LT -II
Withou tCONSU LT -II
1 INSPECTIO NSTART
On Board Diagnosis Logic
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2 CHEC KBATTE RY AN DALTERN ATOR
3 CHEC KJUMPE RCABLE SINS TALL ATION
SEF439Z
4 CHEC KBATTE RY FO RBOOSTER
5 PERFOR MDT CCONFIRM ATIO NPROCEDUR EAGAIN
6 CHEC KELECTRICA LPART SDAMAGE
Diagnostic Procedure (Cont'd)