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EC-454Revision: November 2009
DTC P0603 ECM POWER SUPPLY
2006 QX56
Wiring DiagramUBS00H7C
BBWA2098E
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DTC P0603 ECM POWER SUPPLYEC-455
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Revision: November 2009 2006 QX56
Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
Diagnostic ProcedureUBS00H7D
1. CHECK ECM POWER SUPPLY
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check voltage between ECM terminal 121 and ground with CONSULT-II or tester.
OK or NG
OK >> GO TO 3.
NG >> GO TO 2.
2. DETECT MALFUNCTIONING PART
Check the following.
IPDM E/R connector E121
20A fuse
Harness for open or short between ECM and battery
>> Repair or replace harness or connectors.
3. CHECK INTERMITTENT INCIDENT
Refer to EC-144, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
OK or NG
OK >> GO TO 4.
NG >> Repair or replace harness or connectors.
TER-
MINAL NO. WIRE
COLOR ITEM
CONDITION DATA (DC Voltage)
121 W Power supply for ECM
(Back-up) [Ignition switch: OFF] BATTERY VOLTAGE
(11 - 14V)
Voltage: Battery voltage
MBIB0026E
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EC-456Revision: November 2009
DTC P0603 ECM POWER SUPPLY
2006 QX56
4. PERFORM DTC CONFIRMATION PROCEDURE
With CONSULT-II
1. Turn ignition switch ON.
2. Select “SELF DIAG RESULTS ” mode with CONSULT-II.
3. Touch “ERASE”.
4. Perform DTC Confirmation Procedure.
See EC-453, "
DTC Confirmation Procedure" .
5. Is the 1st trip DTC P0603 displayed again?
With GST
1. Turn ignition switch ON.
2. Select Service $04 with GST.
3. Perform DTC Confirmation Procedure.
See EC-453, "
DTC Confirmation Procedure" .
4. Is the 1st trip DTC P0603 displayed again?
Ye s o r N o
Yes >> GO TO 5.
No >> INSPECTION END
5. REPLACE ECM
1. Replace ECM.
2. Perform initialization of IVIS(NATS) system and registration of all IVIS(NATS) ignition key IDs. Refer to BL-139, "
ECM Re-communicating Function" .
3. Perform EC-77, "
VIN Registration" .
4. Perform EC-78, "
Accelerator Pedal Released Position Learning" .
5. Perform EC-78, "
Throttle Valve Closed Position Learning" .
6. Perform EC-78, "
Idle Air Volume Learning" .
>> INSPECTION END
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DTC P0605 ECMEC-457
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Revision: November 2009 2006 QX56
DTC P0605 ECMPFP:23710
Component DescriptionUBS00H6X
The ECM consists of a microcomputer and connectors for signal
input and output and for power supply. The ECM controls the engine.
On Board Diagnosis LogicUBS00H6Y
This self-diagnosis has one or two trip detection logic.
FAIL-SAFE MODE
ECM enters fail-safe mode when the malfunction A is detected.
DTC Confirmation ProcedureUBS00H6Z
Perform PROCEDURE FOR MALFUNCTION A first. If the 1st trip DTC cannot be confirmed, perform
PROCEDURE FOR MALFUNCTION B. If there is no malfunction on PROCEDURE FOR MALFUNCTION
B, perform PROCEDURE FOR MALFUNCTION C.
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
PROCEDURE FOR MALFUNCTION A
With CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR ” mode with CONSULT-II.
3. If 1st trip DTC is detected, go to EC-458, "
Diagnostic Procedure"
With GST
Follow the procedure “With CONSULT-II” above.
PBIB1164E
DTC No. Trouble diagnosis name DTC detecting conditionPossible cause
P0605
0605 Engine control module A) ECM calculation function is malfunctioning.
ECM
B) ECM EEP-ROM system is malfunctioning.
C) ECM self shut-off function is malfunctioning.
Detected items Engine operation condition in fail-safe mode
Malfunction A
ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx.
5 degrees) by the return spring.
ECM deactivates ASCD operation.
SEF058Y
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EC-458Revision: November 2009
DTC P0605 ECM
2006 QX56
PROCEDURE FOR MALFUNCTION B With CONSULT-II
1. Turn ignition switch ON and wait at least 1 second.
2. Select “DATA MONITOR ” mode with CONSULT-II.
3. Turn ignition switch OFF, wait at least 10 seconds and then turn ON.
4. If 1st trip DTC is detected, go to EC-458, "
Diagnostic Procedure"
.
With GST
Follow the procedure “With CONSULT-II” above.
PROCEDURE FOR MALFUNCTION C
With CONSULT-II
1. Turn ignition switch ON and wait at least 1 second.
2. Select “DATA MONITOR ” mode with CONSULT-II.
3. Turn ignition switch OFF, wait at least 10 seconds and then turn ON.
4. Repeat step 3 for 32 times.
5. If 1st trip DTC is detected, go to EC-458, "
Diagnostic Procedure"
.
With GST
Follow the procedure “With CONSULT-II” above.
Diagnostic ProcedureUBS00H70
1. INSPECTION START
With CONSULT-II
1. Turn ignition switch ON.
2. Select “SELF DIAG RESULTS ” mode with CONSULT-II.
3. Touch “ERASE”.
4. Perform DTC Confirmation Procedure.
See EC-457, "
DTC Confirmation Procedure" .
5. Is the 1st trip DTC P0605 displayed again?
With GST
1. Turn ignition switch ON.
2. Select Service $04 with GST.
3. Perform DTC Confirmation Procedure.
See EC-457, "
DTC Confirmation Procedure" .
4. Is the 1st trip DTC P0605 displayed again?
Ye s o r N o
Yes >> GO TO 2.
No >> INSPECTION END
SEF058Y
SEF058Y
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DTC P0605 ECMEC-459
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2. REPLACE ECM
1. Replace ECM.
2. Perform initialization of IVIS(NATS) system and registration of all IVIS(NATS) ignition key IDs. Refer to BL-139, "
ECM Re-communicating Function" .
3. Perform EC-77, "
VIN Registration" .
4. Perform EC-78, "
Accelerator Pedal Released Position Learning" .
5. Perform EC-78, "
Throttle Valve Closed Position Learning" .
6. Perform EC-78, "
Idle Air Volume Learning" .
>> INSPECTION END
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EC-460Revision: November 2009
DTC P0643 SENSOR POWER SUPPLY
2006 QX56
DTC P0643 SENSOR POWER SUPPLYPFP:18919
On Board Diagnosis LogicUBS00H9B
This self-diagnosis has the one trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, ECM enters fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureUBS00H9C
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR ” mode with CONSULT-II.
3. Start engine and let it idle for 1 second.
4. If DTC is detected, go to EC-463, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0643
0643 Sensor power supply circuit
short ECM detects a voltage of power source
for sensor is excessively low or high.
Harness or connectors
(APP sensor 1 circuit is shorted.)
(PSP sensor circuit is shorted.)
(Refrigerant pressure sensor circuit is
shorted.)
(EVAP control system pressure sensor circuit
is shorted.)
Accelerator pedal position sensor
Power steering pressure sensor
Refrigerant pressure sensor
EVAP control system pressure sensor
Engine operation condition in fail-safe mode
ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) b y the return
spring.
SEF058Y
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DTC P0643 SENSOR POWER SUPPLYEC-461
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Revision: November 2009 2006 QX56
Wiring DiagramUBS00H9D
BBWA2123E