2009 INFINITI QX56 200

DIAGNOSIS AND REPAIR WORKFLOWSTR-7
< BASIC INSPECTION >
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YES >> GO TO 8.
NO >> Repair as needed.
8.“S” CONNECTOR CIRCUIT INSPECTION
Check “S” connector circuit. Refer to STR-11, "
Diagnosis Procedure".
Is
“S” connector circuit normal?
YES >> GO TO 9.
NO >> Repair as needed.
9.ENGINE ROTATION STATUS
Check that the engine can be rotated by hand.
Does the engine turn freely by hand?
YES >> Replace starter motor.
NO >> Perform further diagnosis of engine mechanical or powertrain mechanism. Refer to EM or TM
sections. Once resolved, perform battery test agai n. Refer to diagnostic station instruction man-
ual.
Revision: December 20092009 QX56

STR-8
< FUNCTION DIAGNOSIS >
STARTING SYSTEM
FUNCTION DIAGNOSIS
STARTING SYSTEM
System DiagramINFOID:0000000003771788
System DescriptionINFOID:0000000003771789
The starter motor plunger closes and provides a closed circuit between the battery and the starter motor. The
starter motor is grounded to the cylinder block. With power and ground supplied, the starter motor operates.
Component Parts LocationINFOID:0000000003771790
ALBIA0416GB
1. A/T assembly F9 (with built in TCM
F502) 2. IPDM E/R E119, E120, E122, E124 3. BCM M18 (view with instrument panel
lower LH panel removed)
AWBIA0127ZZ
Revision: December 20092009 QX56

STARTING SYSTEMSTR-9
< FUNCTION DIAGNOSIS >
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Component DescriptionINFOID:0000000003771791
Component part
Description
TCM TCM supplies power to the starter relay inside the IPDM E/R when
the selector lever is shifted to the P or N position.
BCM BCM sends a starter request signal to the CPU of the IPDM E/R
over the CAN communication lines.
IPDM E/R CPU inside IPDM E/R operates the starter relay at the request of
the BCM over the CAN communication lines.
Starter motor The starter motor plunger closes and the motor is supplied with
battery power, which in turn cranks the engine, when the “S” ter-
minal is supplied with electric power.
Revision: December 20092009 QX56

STR-10
< COMPONENT DIAGNOSIS >
B TERMINAL CIRCUIT
COMPONENT DIAGNOSIS
B TERMINAL CIRCUIT
DescriptionINFOID:0000000003771792
Terminal "2" (B) is constantly supplied with battery power.
Diagnosis ProcedureINFOID:0000000003771793
CAUTION:
Perform diagnosis under the condition that the engine cannot start by the following procedure.
1. Remove fuel pump fuse.
2. Crank or start the engine (where possible) until the fuel pressure is depleted.
1.CHECK TERMINAL 2 POWER SUPPLY VOLTAGE
1. Turn ignition switch OFF.
2. Make sure that starter motor connector F27 terminal 2 connection is clean and tight.
3. Check voltage between starter motor connector F27 terminal 2
and ground.
Is there battery voltage present?
YES >> GO TO 2
NO >> Check harness between battery and starter motor for open circuit.
2.CHECK BATTERY CABLE (VOLTAGE DROP TEST)
1. Shift the transmission into park or neutral.
2. Check voltage between battery positive terminal and starter motor connector F27 terminal 2 while cranking the engine.
Is the voltage drop less than 0.2V?
YES >> GO TO 3
NO >> Check harness between the battery and the starter motor for high resistance.
3.CHECK GROUND CIRCUIT STATUS (VOLTAGE DROP TEST)
Check voltage between starter motor case and battery negative ter-
minal while cranking the engine.
Is the voltage drop less than 0.2V?
YES >> Terminal 2 circuit is OK. Further inspection necessary. Refer to STR-5, "
Work Flow".
NO >> Check the starter motor case to engine mounting for high resistance.
(+) (-)Condition Voltage
Connector Terminal
F27 2 Ground While cranking the
engine Battery voltage
AWBIA0122GB
(+)
(-)Condition Voltage
Connector Terminal
F27 2 Battery (+)
terminal While cranking the
engine Less than 0.2V
AWBIA0123GB
(+)
(-)Condition Voltage
Starter motor case Battery (-) terminal
While cranking the
engine Less than 0.2V
AWBIA0124GB
Revision: December 20092009 QX56

S CONNECTOR CIRCUITSTR-11
< COMPONENT DIAGNOSIS >
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S CONNECTOR CIRCUIT
DescriptionINFOID:0000000003771794
Terminal "1" (S) is the power supply for the starter mo
tor magnetic switch. Terminal 1 is supplied with power
when the ignition switch is turned to the START position while the selector lever is in the P or N position.
Diagnosis ProcedureINFOID:0000000003771795
CAUTION:
Perform diagnosis under the cond ition that engine cannot start by the following procedure.
1. Remove fuel pump fuse.
2. Crank or start the engine (where possi ble) until the fuel pressure is released.
1.CHECK STARTER MOTOR MAGNETIC SWITCH CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect starter motor connector F28.
3. Shift transmission into park or neutral.
4. Check voltage between starter motor harness connector F28 terminal 1 and ground with the ignition switch in START.
Is battery voltage present?
YES >> Magnetic switch circuit is OK. Further inspection necessary. Refer to STR-5, "Work Flow".
NO >> GO TO 2
2.CHECK CONNECTOR
1. Turn ignition switch OFF.
2. Check the IPDM E/R harness connector E120 and starter motor harness connector F28 for damage, bent pins and loose connections.
Is the inspection result normal?
YES >> GO TO 3
NO >> Repair the terminal and connector.
3.CHECK HARNESS CONTI NUITY (OPEN CIRCUIT)
1. Disconnect IPDM E/R connector E120 and starter motor con- nector F28.
2. Check continuity between starter motor harness connector F28 (A) terminal 1 and IPDM E/R harness connector E120 (B) termi-
nal 19.
3. Check continuity between starter motor harness connector F28 (A) terminal 1 and ground.
Are the continuity test results as specified?
YES >> Further inspection necessary. Refer to STR-5, "Work Flow".
NO >> Repair the harness.
(+) (-)Condition Voltage
Connector Terminal
F28 1 Ground Ignition switch in
START Battery voltage
AWBIA0125GB
AB
Continuity
Connector Terminal Connector Terminal
F28 1E120 19 Yes
A —Con tin uit y
Connector Terminal
F28 1Ground No
AWBIA0126GB
Revision: December 20092009 QX56

STR-12
< COMPONENT DIAGNOSIS >
STARTING SYSTEM
STARTING SYSTEM
Wiring DiagramINFOID:0000000003771796
ABBWA0004GB
Revision: December 20092009 QX56

STARTING SYSTEMSTR-13
< COMPONENT DIAGNOSIS >
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AABIA0056GB
Revision: December 20092009 QX56

STR-14
< COMPONENT DIAGNOSIS >
STARTING SYSTEM
AABIA0057GB
Revision: December 20092009 QX56