2004 INFINITI QX56 Air

TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
ACS-37
[ICC]
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ACS
Revision: August 20072004 QX56
DTC 11 CONTROL UNITEKS007X3
1. DIAGNOSTIC CHECK
1. Are any items other than “DTC 11 CONTROL UNIT” indicated on self-diagnosis display?
YES or NO
YES >> Repair or replace applicable item. Erase DTC and perform ICC system running test. Then perform
self-diagnosis of ICC system again.
NO >> Replace ICC unit. Refer to ACS-59, "
ICC Unit" . Erase DTC and perform ICC system running
test. Then perform self-diagnosis of ICC system again.
DTC 12 VDC CONTROL UNITEKS008DH
1. DIAGNOSIS CHECK
With CONSULT-II

Perform self-diagnosis of ABS actuator and electric unit (control unit). Is malfunction indicated?
YES or NO
YES >> Repair or replace applicable item. Erase DTC and perform ICC system running test. Then per-
form self-diagnosis of ICC system again.
NO >> GO TO 2.
2. CHECK CONNECTOR ICC UNIT AND ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
1. Turn ignition switch OFF.
2. Disconnect connectors of ICC unit and ABS actuator and electric unit (control unit), and connect them
securely again. Then erase DTC. Then, perform self-diagnosis of ICC system again.
OK or NG
OK >> Poor connector connection. Check connector housing for disconnected, loose, bent and col-
lapsed terminals. If any malfunction is detected, repair applicable part. After repair, erase DTC
and perform ICC system running test. Then perform self-diagnosis of ICC system again.
NG >> GO TO 3.
98 GEAR POSITION××

TCM malfunction

AT turbine revolution sensor mal-
function

AT vehicle speed sensor mal-
functionACS-49
102 LASER STAIN×× ×
ICC sensor body window has
contaminationACS-49
103 LASER SENSOR FAIL×× ×
ICC sensor internal malfunctionACS-50
104 LASER AIMING INCMP×× ×
Laser beam aiming of ICC sensor
is not adjustedACS-50
107 LASER COMM FAIL×× ×

CAN data received by ICC sen-
sor is strange (from ICC unit,
combination meter or ECM)ACS-51
109 LASER HIGH TEMP×× ×
Temperature around ICC sensor
is excessively highACS-51
DTC
No.CONSULT-II screen termsICC sys-
tem
warning
lampFail-safe
Malfunctions detected where...Refer-
ence
page Vehicle-
to-vehi-
cle dis-
tance
control
modeConven-
tional
(fixed
speed)
cruise
control
modeBrake
assist
(with pre-
view
function)

ACS-38
[ICC]
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
Revision: August 20072004 QX56
3. CHECK HARNESS BETWEEN ICC UNIT AND ABS ACTUATOR AND ELECTRIC UNIT (CONTROL
UNIT)
1. Turn ignition switch OFF.
2. Disconnect connectors of ICC unit and ABS actuator and elec-
tric unit (control unit).
3. Check continuity between ICC unit harness connector B13 ter-
minal 10 (V/R) and ABS actuator and electric unit (control unit)
connector E125 terminal 7 (V/R).
OK or NG
OK >> Replace ICC unit. Refer to ACS-59, "ICC Unit" . Erase
DTC and perform ICC system running test. Then per-
form self-diagnosis of ICC system again.
NG >>

Repair harness between ICC unit and ABS actuator and electric unit (control unit).

After repair, erase DTC and perform ICC system running test. Then, perform self-diagnosis of
ICC system again.
DTC 20 CAN COMM CIRCUITEKS007X4
1. CHECK CAN COMMUNICATION
With CONSULT-II
1. Perform self-diagnosis.
2. Print self-diagnostic result.
>> After printing self-diagnostic result, go to “CAN system”. Refer to LAN-3, "
Precautions When
Using CONSULT-II" .
DTC 31 POWER SUPPLY CIR 1, DTC 34 POWER SUPPLY CIR 2EKS007X5
1. CHECK ICC UNIT CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect ICC unit connector and connect it securely again. Then erase DTC. Then perform self-diagno-
sis of ICC system again.
OK or NG
OK >> GO TO 2.
NG >>

Poor connector connection.

Check connector. (Check connector housing for disconnected, loose, bent, and collapsed ter-
minals. If any malfunction is detected, repair applicable part.) After repair, erase DTC, and per-
form ICC running test. Then perform self-diagnosis of ICC system again.
2. CHECK POWER SUPPLY CIRCUIT FOR ICC UNIT
1. Turn ignition switch ON.
2. Check voltage between ICC unit harness connector B17 termi-
nal 33 (R/B), 42 (R/B) and ground.
OK or NG
OK >> GO TO 3.
NG >>

Repair ICC unit power supply harness.

After repair, erase DTC and perform ICC system run-
ning test. Then, perform self-diagnosis of ICC system
again. Continuity should exist.
WKIA2042E
Battery voltage should exist.
SKIA11 73 E

TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
ACS-39
[ICC]
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ACS
Revision: August 20072004 QX56
3. CHECK GROUND CIRCUIT FOR ICC UNIT
1. Turn ignition switch OFF.
2. Disconnect ICC unit connectors.
3. Check continuity between ICC unit harness connector B13 ter-
minal 19 (B), 20 (B), B17 terminal 46 (B) and ground.
OK or NG
OK >> Replace ICC unit, Refer to ACS-59, "ICC Unit" . Erase
DTC, and perform ICC system running test. Then per-
form self-diagnosis of ICC system again.
NG >>

Repair ICC unit ground harness.

After repair, erase DTC and perform ICC system running test. Then perform self-diagnosis of
ICC system again.
DTC 41 VHCL SPEED SE CIRCEKS007X6
1. PERFORM ICC UNIT SELF-DIAGNOSIS
1. Perform self-diagnosis. Is “DTC 43 VDC/TCS/ABS CIRC” or “DTC 20 CAN COMM CIRCUIT” indicated in
self-diagnosis item display?
YES or NO
YES >> Repair or replace applicable item. Erase DTC and perform ICC system running test. Then perform
self-diagnosis of ICC system again.
NO >> GO TO 2.
2. CHECK AT VEHICLE SPEED SENSOR
With CONSULT-II

With data monitor, check “VHCL SPD AT”.
OK or NG
OK >> Replace ICC unit. Refer to ACS-59, "ICC Unit" . Erase DTC and perform ICC system running
test. Then perform self-diagnosis of ICC system again.
NG >>

Check TCM.

After repair, erase DTC and perform ICC system running test. Then, perform self-diagnosis of
ICC system again.
DTC 43 VDC/TCS/ABS CIRCEKS007X7
1. DIAGNOSIS CHECK 1
With CONSULT-II

Perform self-diagnosis. Is “CAN COMM CIRCUIT” indicated?
YES or NO
YES >> Repair or replace applicable item. Erase DTC and perform ICC system running test. Then perform
self-diagnosis of ICC system again.
NO >> GO TO 2.
2. DIAGNOSIS CHECK 2
With CONSULT-II

Perform self-diagnosis of ABS actuator and electric unit (control unit). Is malfunction indicated?
YES or NO
YES >> Repair or replace applicable item. Erase DTC and perform ICC system running test. Then perform
self-diagnosis of ICC system again.
NO >> Replace ICC unit. Refer to ACS-59, "
ICC Unit" . Erase DTC and perform ICC system running
test. Then perform self-diagnosis of ICC system again. Continuity should exist.
SKIA6650E

ACS-40
[ICC]
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
Revision: August 20072004 QX56
DTC 45 BRAKE SW/STOP L SWEKS007X8
1. CHECK CONNECTORS FOR ICC UNIT
1. Turn ignition switch OFF.
2. Disconnect ICC unit connectors, and connect them securely again. Then erase DTC. Then, perform self-
diagnosis of ICC system again.
OK or NG
OK >>
Poor connector connection.

Check connectors. (Check connectors housing for disconnected, loose, bent, and collapsed
terminals. If any malfunction is detected, repair applicable part.) After repair, erase DTC, and
perform ICC system running test. Then perform self-diagnosis of ICC system again.
NG >> GO TO 2.
2. CHECK STOP LAMP SWITCH AND ICC BRAKE SWITCH
With CONSULT-II

With data monitor, check if “STOP LAMP SW” and “BRAKE SW” are operating normally.
OK or NG
OK >> Replace ICC unit. Refer to ACS-59, "ICC Unit" . Erase DTC and perform ICC system running
test. Then perform self-diagnosis of ICC system again.
NG >>

BRAKE SW: GO TO 3.

STOP LAMP SW: GO TO 5.
3. ICC BRAKE SWITCH INSTALLATION AND ADJUSTMENT INSPECTION

Check ICC brake switch for proper installation and adjust if necessary. Refer to BR-6, "BRAKE PEDAL" .
OK or NG
OK >> GO TO 4.
NG >> After adjustment, erase DTC and perform ICC system running test. Then perform self-diagnosis
of ICC system again.
4. CHECK ICC BRAKE SWITCH

Check ICC brake switch. Refer to ACS-58, "ICC Brake Switch and Stop Lamp Switch" .
OK or NG
OK >> Replace ICC unit. Refer to ACS-59, "ICC Unit" . Erase DTC and perform ICC system running
test. Then perform self-diagnosis of ICC system again.
NG >> Replace ICC brake switch. Erase DTC and perform ICC system running test. Then perform self-
diagnosis of ICC system again.
5. CHECK STOP LAMP ILLUMINATION

Check stop lamp illumination.
OK or NG
OK >> GO TO 6.
NG >>

Check stop lamp circuit.

After repair, erase DTC and perform ICC system running test. Then, perform self-diagnosis of
ICC system again.

TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
ACS-41
[ICC]
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Revision: August 20072004 QX56
6. CHECK ICC BRAKE HOLD RELAY
1. Turn ignition switch OFF.
2. Remove ICC brake hold relay.
3. Check continuity between terminals of ICC brake hold relay.
OK or NG
OK >> GO TO 7.
NG >> Replace ICC brake hold relay. Erase DTC and perform
ICC system running test. Then perform self-diagnosis of
ICC system again.
7. CHECK ICC BRAKE HOLD RELAY CIRCUIT
1. Disconnect connectors of ICC unit and stop lamp switch.
2. Check continuity between ICC unit harness connector B17 ter-
minal 38 (R/G) and ICC brake hold relay harness connector
E134 terminal 7 (R/G).
3. Check continuity between ICC unit harness connector B17 ter-
minal 38 (R/G) and stop lamp switch harness connector E38 ter-
minal 4 (R/G).
OK or NG
OK >> Replace ICC unit. Refer to ACS-59, "ICC Unit" . Erase
DTC and perform ICC system running test. Then perform self-diagnosis of ICC system again.
NG >>

Repair harness between ICC unit and ICC brake hold relay or stop lamp switch.

After repair, erase DTC and perform ICC system running test. Then, perform self-diagnosis of
ICC system again.
DTC 46 OPERATION SW CIRCEKS007X9
1. CHECK ECM CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect ECM connector, and connect it securely again. Then erase DTC. Then, perform self-diagnosis
of ICC system again.
OK or NG
OK >>
Poor connector connection.

Check connector. (Check connector housing for disconnected, loose, bent, and collapsed ter-
minals. If any malfunction is detected, repair applicable part.) After repair, erase DTC, and per-
form ICC system running test. Then perform self-diagnosis of ICC system again.
NG >> GO TO 2.
2. CHECK ICC STEERING SWITCH

Check ICC steering switch. Refer to ACS-58, "ICC Steering Switch" .
OK or NG
OK >> GO TO 3.
NG >> Replace ICC steering switch assembly. Refer to ACS-59, "
ICC Steering Switch" . Erase DTC and
perform ICC system running test. Then perform self-diagnosis of ICC system again. 7 - 6 Continuity should not exist.
4 - 3 Continuity should exist.
SKIA6651E
Continuity should exist.
Continuity should exist.
WKIA3403E

ACS-42
[ICC]
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
Revision: August 20072004 QX56
3. CHECK ICC STEERING SWITCH SIGNAL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect connectors of ECM and spiral cable.
3. Check continuity between ECM harness connectors E16 and
F54 terminals 67 (B), 99 (G/Y) and spiral cable M30 terminal 33
(B), 34 (G/Y).
OK or NG
OK >> GO TO 4.
NG >>

Repair harness between ECM and spiral cable.

Erase DTC and perform ICC system running test. Then, perform self-diagnosis of ICC system
again.
4. CHECK ICC STEERING SWITCH SIGNAL CIRCUIT
1. Disconnect remaining spiral cable connector.
2. Check continuity between spiral cable (to vehicle) harness con-
nector M30 terminal 33, 34 and spiral cable (to switch) harness
connector M102 terminal 14,15.
OK or NG
OK >> Replace ECM. Erase DTC and perform ICC system run-
ning test. Then perform self-diagnosis of ICC system
again.
NG >>

Replace spiral cable. Refer to SRS-47, "Removal
and Installation" .

Erase DTC and perform ICC system running test.
Then, perform self-diagnosis of ICC system again.
DTC 74 LASER BEAM OFF CENTEREKS007XE
1. DIAGNOSTIC CHECK
1. Adjust laser beam aiming. Then erase DTC, and perform ICC system running test. Refer to ACS-12,
"LASER BEAM AIMING ADJUSTMENT" .
2. After that, perform self-diagnosis of ICC system. Is DTC 74 LASER BEAM OFF CNTR indicated?
YES or NO
YES >>
Replace ICC sensor and adjust laser beam aiming. Refer to ACS-59, "ICC Sensor" .

After that, erase DTC and perform ICC system running test. Then perform self-diagnosis of ICC
system again.
NO >> Inspection end.67 - 33, 99 - 34 Continuity should exist.
WKIA1928E
34 - 14, 33 - 15 Continuity should exist.
SKIA5979E

TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
ACS-43
[ICC]
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ACS
Revision: August 20072004 QX56
DTC 90 STOP LAMP RLY FIXEKS007XF
1. CHECK ICC UNIT CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect and check ICC unit connector.
OK or NG
OK >> GO TO 2.
NG >>

Connector malfunction.

After repair, erase DTC, and perform ICC system running test. Then perform self-diagnosis of
system.
2. CHECK STOP LAMP SWITCH AND ICC BRAKE SWITCH
With CONSULT-II
1. Connect ICC unit connector and turn ignition switch ON.
2. With data monitor, check that “STOP LAMP SW” and “BRAKE SW” operate normally.
OK or NG
OK >> GO TO 11.
NG >>

BRAKE SW: GO TO 3.

STOP LAMP SW: GO TO 8.
3. CHECK AND ADJUST ICC BRAKE SWITCH

Check ICC brake switch for proper installation and adjust if necessary. Refer to BR-6, "BRAKE PEDAL" .
OK or NG
OK >> GO TO 4.
NG >> After adjustment, erase DTC and perform ICC system running test. Then perform self-diagnosis
of ICC system again.
4. CHECK ICC BRAKE SWITCH

Check ICC brake switch. Refer to ACS-58, "ICC Brake Switch and Stop Lamp Switch" .
OK or NG
OK >> GO TO 5.
NG >> Replace ICC brake switch. Erase DTC and perform ICC system running test. Then perform self-
diagnosis of ICC system again.
5. CHECK ICC BRAKE HOLD RELAY

Disconnect ICC brake hold relay, and check continuity between
ICC brake hold relay terminal 4 and terminal 3.
OK or NG
OK >> GO TO 6.
NG >> Replace ICC brake hold relay. Erase DTC and perform
ICC system running test. Then perform self-diagnosis of
ICC system again.
Continuity should exist.
SKIA6658E

ACS-44
[ICC]
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
Revision: August 20072004 QX56
6. CHECK HARNESS THROUGH ICC BRAKE HOLD RELAY, ICC BRAKE SWITCH, ICC UNIT
1. Disconnect ICC brake hold relay, ECM and ICC unit harness connectors.
2. Check continuity between ICC brake hold relay harness connec-
tor E134 terminal 4 (L) and ICC unit harness connector B17 ter-
minal 29 (BR/W).
3. Check continuity between ICC unit harness connector B17 ter-
minal 29 (BR/W) and ground.
OK or NG
OK >> GO TO 7.
NG >>

Repair harness between ICC brake hold relay and
ICC brake switch.

Repair harness between ICC brake switch and ICC unit.

After repair, erase DTC and perform ICC system running test. Then, perform self-diagnosis of
ICC system again.
7. CHECK ICC BRAKE HOLD RELAY POWER SUPPLY CIRCUIT
1. Turn ignition switch ON.
2. Check voltage between ICC brake hold relay harness connector
E134 terminal 3 (R/B) and ground.
OK or NG
OK >> Replace ICC unit. Refer to ACS-59, "ICC Unit" . Erase
DTC and perform ICC system running test. Then per-
form self-diagnosis of ICC system again.
NG >>

Check fuse or ICC brake hold relay power supply sys-
tem harness.

After repair, erase DTC and perform ICC system running test. Then, perform self-diagnosis of
ICC system again.
8. CHECK STOP LAMP SWITCH
1. Turn ignition switch OFF.
2. Check stop lamp switch. Refer to ACS-58, "
ICC Brake Switch and Stop Lamp Switch" .
OK or NG
OK >> GO TO 9.
NG >> Replace stop lamp switch. Erase DTC and perform ICC system running test. Then, perform self-
diagnosis of ICC system again.
9. CHECK ICC BRAKE HOLD RELAY CIRCUIT
1. Disconnect stop lamp switch connector.
2. When brake pedal is not depressed, make sure that stop lamp does not illuminate.
OK or NG
OK >> Replace ICC unit. Refer to ACS-59, "ICC Unit" . Erase DTC and perform ICC system running
test. Then perform self-diagnosis of ICC system again.
NG >> GO TO 10.Continuity should exist.
Continuity should not exist.
WKIA1929E
Battery voltage should exist.
WKIA1930E