Page 1817 of 3383

EC-606Revision: November 2009
FUEL PUMP
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 ProcedureUBS00HDE
1. CHECK OVERALL FUNCTION
1. Turn ignition switch ON.
2. Pinch fuel feed hose with two fingers.
OK or NG
OK >> INSPECTION END
NG >> GO TO 2.
2. CHECK FUEL PUMP POWER SUPPLY CIRCUIT-I
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Turn ignition switch ON.
4. Check voltage between ECM terminal 113 and ground with CONSULT-II or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 3.
TER-
MINAL NO. WIRE
COLOR ITEM
CONDITION DATA (DC Voltage)
11 3 G R F u e l p u m p r e l a y [Ignition switch: ON]
For 1 second after turning ignition switch ON
[Engine is running] 0 - 1.5V
[Ignition switch: ON]
More than 1 second after turning ignition
switch ON. BATTERY VOLTAGE
(11 - 14V)
Fuel pressure pulsation should be felt on the fuel feed
hose for 1 second after ignition switch is turned ON.
BBIA0357E
Voltage: Battery voltage
PBIB1187E
Page 1818 of 3383

FUEL PUMPEC-607
C
DE
F
G H
I
J
K L
M A
EC
Revision: November 2009 2006 QX56
3. CHECK FUEL PUMP POWER SUPPLY CIRCUIT-II
Check voltage between IPDM E/R terminal 46 and ground with
CONSULT-II or tester.
OK or NG
OK >> GO TO 4.
NG >> GO TO 13.
4. DETECT MALFUNCTIONING PART
Check harness for open or short between IPDM E/R and ECM.
>> Repair harness or connectors.
5. CHECK CONDENSER-2 POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Reconnect all harness connectors disconnected.
3. Disconnect condenser-2 harness connector.
4. Turn ignition switch ON.
5. Check voltage between condenser-2 terminal 1 and ground with CONSULT-II or tester.
6. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 8.
NG >> GO TO 6.
6. CHECK 15A FUSE
1. Turn ignition switch OFF.
2. Disconnect 15A fuse.
3. Check 15A fuse.
OK or NG
OK >> GO TO 7.
NG >> Replace fuse. Voltage: Battery voltage
PBIB2656E
BBIA0388E
Voltage: Battery voltage should exist for 1 sec-
ond after ignition switch is turned ON.
PBIB0624E
Page 1819 of 3383

EC-608Revision: November 2009
FUEL PUMP
2006 QX56
7. CHECK CONDENSER-2 POWER SUPPLY CIRCUIT-II FOR OPEN AND SHORT
1. Disconnect IPDM E/R harness connector E119.
2. Check harness continuity between IPDM E/R terminal 13 and condenser-2 terminal 1. Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 13.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
8. CHECK CONDENSER-2 GROUND CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between condenser-2
+ terminal 2 and ground.
Refer to Wiring Diagram.
2. Also check harness for short to power.
OK or NG
OK >> GO TO 9.
NG >> Repair open circuit or short to power in harness or connectors.
9. CHECK CONDENSER-2
Refer to EC-609, "
Component Inspection" .
OK or NG
OK >> GO TO 10.
NG >> Replace condenser-2.
10. CHECK FUEL PUMP POWER SUPPLY AND GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect “fuel level sensor unit and fuel pump ” harness con-
nector.
3. Disconnect IPDM E/R harness connector E119.
4. Check harness continuity between IPDM E/R terminal 13 and “fuel level sensor unit and fuel pump” terminal 1, “fuel level sen-
sor unit and fuel pump ” terminal 3 and ground.
Refer to Wiring Diagram.
5. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 12.
NG >> GO TO 11. Continuity should exist.
Continuity should exist.
Continuity should exist.
BBIA0583E
Page 1820 of 3383

FUEL PUMPEC-609
C
DE
F
G H
I
J
K L
M A
EC
Revision: November 2009 2006 QX56
11 . DETECT MALFUNCTIONING PART
Check the following.
Harness connectors E41, C1
Harness for open or short between fuel pump and IPDM E/R
Harness for open or short between fuel pump and ground
>> Repair open circuit or short to ground or short to power in harness or connectors.
12. CHECK FUEL PUMP
Refer to EC-609, "
Component Inspection" .
OK or NG
OK >> GO TO 13.
NG >> Replace “fuel level sensor unit and fuel pump ”.
13. CHECK INTERMITTENT INCIDENT
Refer to EC-144, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
OK or NG
OK >> Replace IPDM E/R.
NG >> Repair or replace harness or connectors.
Component InspectionUBS00HDF
FUEL PUMP
1. Disconnect “fuel level sensor unit and fuel pump ” harness connector.
2. Check resistance between fuel level sensor unit and fuel pump terminals 1 and 3.
CONDENSER-2
1. Turn ignition switch OFF.
2. Disconnect condenser-2 harness connector.
3. Check resistance between condenser-2 terminals as 1 and 2.
Removal and InstallationUBS00HDG
FUEL PUMP
Refer to FL-6, "FUEL LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY" .
Resistance: 0.2 - 5.0
Ω [at 25 °C (77 °F)]
SEC918C
Resistance Above 1 MΩ at 25 °C (77 °F)
PBIB0794E
Page 1821 of 3383
EC-610Revision: November 2009
ICC BRAKE SWITCH
2006 QX56
ICC BRAKE SWITCHPFP:25320
Component DescriptionUBS00L23
When depress on the brake pedal, ICC brake switch is turned OFF
and stop lamp switch is turned ON. ECM detects the state of the
brake pedal by this input of two kinds (ON/OFF signal)
Refer to ACS-6, "
DESCRIPTION" for the ICC function.
CONSULT-II Reference Value in Data Monitor ModeUBS00L24
Specification data are reference values.
BBIA0470E
MONITOR ITEM CONDITIONSPECIFICATION
BRAKE SW 1
(ICC brake switch)
Ignition switch: ON Brake pedal: Fully released
ON
Brake pedal: Slightly depressed OFF
BRAKE SW 2
(Stop lamp switch)
Ignition switch: ON Brake pedal: Fully released
OFF
Brake pedal: Slightly depressed ON
Page 1822 of 3383
ICC BRAKE SWITCHEC-611
C
DE
F
G H
I
J
K L
M A
EC
Revision: November 2009 2006 QX56
Wiring DiagramUBS00L25
BBWA2128E
Page 1823 of 3383

EC-612Revision: November 2009
ICC BRAKE SWITCH
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 ProcedureUBS00L26
1. CHECK OVERALL FUNCTION-I
With CONSULT-II
1. Turn ignition switch ON.
2. Select “BRAKE SW1 ” in “DATA MONITOR ” mode with CON-
SULT-II.
3. Check “BRAKE SW1 ” indication under the following conditions.
Without CONSULT-II
1. Turn ignition switch ON.
2. Check voltage between ECM terminal 108 and ground under the following conditions.
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
TER-
MINAL NO. WIRE
COLOR ITEM
CONDITION DATA (DC Voltage)
101 R/W Stop lamp switch [Ignition switch: OFF]
Brake pedal: Fully released
Approximately 0V
[Ignition switch: OFF]
Brake pedal: Slightly depressed BATTERY VOLTAGE
(11 - 14V)
108 BR/W ICC brake switch [Ignition switch: ON]
Brake pedal: Slightly depressed
Approximately 0V
[Ignition switch: ON]
Brake pedal: Fully released BATTERY VOLTAGE
(11 - 14V)
CONDITION
INDICATION
Brake pedal: Slightly depressed OFF
Brake pedal: Fully released ON
SEC011D
CONDITIONVOLTAGE
Brake pedal: Slightly depressed Approximately 0V
Brake pedal: Fully released Battery voltage
MBIB0061E
Page 1824 of 3383
ICC BRAKE SWITCHEC-613
C
DE
F
G H
I
J
K L
M A
EC
Revision: November 2009 2006 QX56
2. CHECK OVERALL FUNCTION-II
With CONSULT-II
Check “BRAKE SW2 ” indication in “DATA MONITOR ” mode.
Without CONSULT-II
Check voltage between ECM terminal 101 and ground under the fol-
lowing conditions.
OK or NG
OK >> INSPECTION END
NG >> GO TO 10.
3. CHECK DTC WITH ICC UNIT
Refer to ACS-36, "
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS" .
OK or NG
OK >> GO TO 4.
NG >> Repair or replace.
CONDITION INDICATION
Brake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
SEC013D
CONDITIONVOLTAGE
Brake pedal: Fully released Approximately 0V
Brake pedal: Slightly depressed Battery voltage
PBIB1537E