Infiniti FX35, FX50 (S51). Manual - part 310

CCS-60

< DTC/CIRCUIT DIAGNOSIS >

[ICC (FULL SPEED RANGE)]

C1A04 ABS/TCS/VDC SYSTEM

>> WORK END

CCS

C1A05 BRAKE SW/STOP LAMP SW

CCS-61

< DTC/CIRCUIT DIAGNOSIS >

[ICC (FULL SPEED RANGE)]

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C1A05 BRAKE SW/STOP LAMP SW

Description

INFOID:0000000005501589

• ICC brake switch is turned OFF and stop lamp switch is turned ON, when depressing the brake pedal. 
• ICC brake switch signal and stop lamp switch signal are input to ECM. These signals are transmitted from

ECM to ICC sensor integrated unit via CAN communication. 

DTC Logic

INFOID:0000000005501590

DTC DETECTION LOGIC

NOTE:
If DTC “C1A05” is detected along with DTC “U1000”, first diagnose the DTC “U1000”. Refer to 

CCS-137,

"DTC Logic"

. 

Diagnosis Procedure

INFOID:0000000005501591

1.

CHECK SELF-DIAGNOSIS RESULTS

1.

Perform “All DTC Reading” with CONSULT-III. 

2.

Check if the “U1000” is detected other than “C1A05” in “Self Diagnostic Result” of “ICC”. 

Is “U1000” detected?

YES

>> Perform the CAN communication system inspection. Repair or replace the malfunctioning parts.

Refer to 

CCS-137, "DTC Logic"

. 

NO

>> GO TO 2.

2.

CHECK STOP LAMP SWITCH AND ICC BRAKE SWITCH

Check that “STOP LAMP SW” and “BRAKE SW” operate normally in “DATA MONITOR” of “ICC”. 
Is the inspection result normal?

YES

>> GO TO 12.

NO-1

>> When “BRAKE SW” operation is malfunctioning: GO TO 3.

NO-2

>> When “STOP LAMP SW” operation is malfunctioning: GO TO 8.

3.

CHECK ICC BRAKE SWITCH INSTALLATION

1.

Turn ignition switch OFF.

2.

Check ICC brake switch for correct installation. Refer to 

BR-7, "Inspection and Adjustment"

. 

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Adjust ICC brake switch installation. Refer to 

BR-7, "Inspection and Adjustment"

. 

4.

ICC BRAKE SWITCH INSPECTION

1.

Disconnect ICC brake switch connector. 

2.

Check ICC brake switch. Refer to 

CCS-64, "Component Inspection (ICC Brake Switch)"

. 

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Replace ICC brake switch. 

DTC

(On board dis-

play)

Trouble diagnosis 

name

DTC detecting condition

Possible causes

C1A05

(5)

BRAKE SW/STOP L 
SW

If ICC sensor integrated unit receives the ICC 
brake switch signal ON status during the stop 
lamp switch signal ON status

• Stop lamp switch circuit
• ICC brake switch circuit
• Stop lamp switch
• ICC brake switch
• Incorrect stop lamp switch installa-

tion

• Incorrect ICC brake switch installa-

tion

• ECM

CCS-62

< DTC/CIRCUIT DIAGNOSIS >

[ICC (FULL SPEED RANGE)]

C1A05 BRAKE SW/STOP LAMP SW

5.

CHECK ICC BRAKE HOLD RELAY

1.

Remove ICC brake hold relay. 

2.

Check for continuity between ICC brake hold relay terminals. 

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> Replace ICC brake hold relay. 

6.

CHECK HARNESS BETWEEN ICC BRAKE HOLD RELAY AND ICC BRAKE SWITCH

1.

Check for continuity between ICC brake hold relay harness connector and ICC brake switch harness con-
nector. 

2.

Check for continuity between ICC brake hold relay harness connector and ground. 

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Repair the harnesses or connectors.

7.

CHECK HARNESS BETWEEN ECM AND ICC BRAKE SWITCH

1.

Disconnect ECM connector. 

2.

Check for continuity between the ECM harness connector and ICC brake switch harness connector. 

VQ35HR

VK50VE

3.

Check for continuity between ECM harness connector and ground.

VQ35HR

VK50VE

Is the inspection result normal?

ICC brake hold relay

Continuity

Terminal

3

4

Existed

ICC brake hold relay

ICC brake switch

Continuity

Connector

Terminal

Connector

Terminal

E91

4

E114

1

Existed

ICC brake hold relay

Ground

Continuity

Connector

Terminal

E91

4

Not existed

ECM

ICC brake switch

Continuity

Connector

Terminal

Connector

Terminal

M107

126

E114

2

Existed

ECM

ICC brake switch

Continuity

Connector

Terminal

Connector

Terminal

M160

117

E114

2

Existed

ECM

Ground

Continuity

Connector

Terminal

M107

126

Not existed

ECM

Ground

Continuity

Connector

Terminal

M160

117

Not existed

CCS

C1A05 BRAKE SW/STOP LAMP SW

CCS-63

< DTC/CIRCUIT DIAGNOSIS >

[ICC (FULL SPEED RANGE)]

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YES

>> GO TO 12.

NO

>> Repair the harnesses or connectors.

8.

CHECK STOP LAMP FOR ILLUMINATION

Check the stop lamp for illumination. 

Is the inspection result normal?

YES

>> GO TO 9.

NO

>> Repair the stop lamp circuit. 

9.

CHECK ICC BRAKE HOLD RELAY

1.

Turn ignition switch OFF.

2.

Remove ICC brake hold relay. 

3.

Check for continuity between ICC brake hold relay terminals. 

Is the inspection result normal?

YES

>> GO TO 10.

NO

>> Replace ICC brake hold relay. 

10.

CHECK HARNESS BETWEEN ECM AND ICC BRAKE HOLD RELAY

1.

Disconnect ECM, rear combination lamp, and high-mounted stop lamp connectors. 

2.

Check for continuity between the ECM harness connector and ICC brake hold relay harness connector. 

VQ35HR

VK50VE

3.

Check for continuity between ECM harness connector and ground. 

VQ35HR

VK50VE

Is the inspection result normal?

YES

>> GO TO 11.

NO

>> Repair the harnesses or connectors.

11.

CHECK HARNESS BETWEEN BRAKE BOOSTER CONTROL UNIT AND ICC BRAKE HOLD RELAY

1.

Disconnect brake booster control unit connector. 

2.

Check for continuity between the brake booster control unit harness connector and brake hold relay har-
ness connector. 

ICC brake hold relay

Continuity

Terminal

3

4

Existed

7

6

Not  existed

ECM

ICC brake hold relay

Continuity

Connector

Terminal

Connector

Terminal

M107

122

E91

6

Existed

ECM

ICC brake hold relay

Continuity

Connector

Terminal

Connector

Terminal

M160

110

E91

6

Existed

ECM

Ground

Continuity

Connector

Terminal

M107

122

Not existed

ECM

Ground

Continuity

Connector

Terminal

M160

110

Not existed