Suzuki GSX-R1000. Service Manual - part 11

1A-98 Engine General Information and Diagnosis: 

Check 4

1) Click the button (6) and increase the “Spec” (2) to 1 

900 rpm.

2) Check that the “Desired idle speed” (3) is approx. 1 

900 rpm.

3) Check that the “Engine speed” (7) is close to 1 900 

rpm.

NOTE

Be careful not to increase the “Spec” to 2 000 
rpm, or the “Engine speed” may reach the 
upper limit.

 

If the ISC valve does not function properly, inspect the 
ISC valve or replace the ISC valve. Refer to “DTC “C40” 
(P0505 / P0506 / P0507): ISC Valve Circuit Malfunction” 
(Page 1A-94) or “Throttle Body Disassembly and 
Assembly” in Section 1D (Page 1D-11).

DTC “C41” (P0230-H/L): FP Relay Circuit Malfunction

B947H11104025

Detected Condition and Possible Cause

Wiring Diagram

ECM coupler (Harness side)

2

6

I947H1110158-01

3

7

I947H1110159-01

Detected Condition

Possible Cause

C41

No voltage is applied to fuel pump.

• Fuel pump relay circuit open or short.

• Fuel pump relay malfunction.

P0230

H

Voltage is applied to fuel pump although 
fuel pump relay is turned OFF.

• Fuel pump relay switch circuit is shorted to power 

source.

• Faulty pump relay (switch side).

L

No voltage is applied to fuel pump 
although fuel pump relay is turned ON.

• Fuel pump relay coil circuit open or short.

• Faulty pump relay (coil side).

ECM

Side-stand
relay

Engine stop 
switch

Fuel pump  
relay

Fuel pump

Ignition  
switch

M

Y/R

VM

FP relay

R/BI

O/W

Y/B

To side-stand
switch

24

40

I837H1110088-01

1

2

3

4

5

6

7

8

9 10 11 12

13 14 15 16 17 18 19 20 21 22 23 24

25 26 27 28 29 30 31 32 33 34 35 36

37 38 39 40 41 42 43 44 45 46 47 48

49 50 51 52 53 54 55 56 57 58 59 60

61 62 63 64 65 66 67 68 69 70 71 72

I837H1110007-02

Engine General Information and Diagnosis:  1A-99

Troubleshooting

CAUTION

!

 

When using the multi-circuit tester, do not strongly touch the terminal of the ECM coupler with a 
needle pointed tester probe to prevent terminal damage.

 

NOTE

After repairing the trouble, clear the DTC using SDS tool. Refer to “Use of SDS Diagnosis Reset 
Procedures” (Page 1A-14).

 

C41 (Use of mode select switch)

Step

Action

Yes

No

1

1) Turn the ignition switch OFF.

2) Remove the frame covers. Refer to “Exterior Parts 

Removal and Installation” in Section 9D (Page 9D-6).

3) Check the FP relay coupler (1) for loose or poor 

contacts. 
If OK, then check the FP relay. Refer to “Fuel Pump 
Relay Inspection” in Section 1G (Page 1G-7).

Is the FP relay OK?

• ECM power input 

signal malfunction.

Refer to “DTC “C41” 
(P2505): ECM Power 
Input Signal 
Malfunction” 
(Page 1A-101).

• Y/B or O/W wire open 

or short or poor “40” 
connection.

• Y/R or R/Bl wire 

open, shorted or poor 
“24” connection.

• If wire and 

connection are OK, 
intermittent trouble or 
faulty ECM.

• Recheck each 

terminal and wire 
harness for open 
circuit and poor 
connection.

• Replace the ECM 

with a known good 
one, and inspect it 
again. Refer to “ECM 
Removal and 
Installation” in 
Section 1C 
(Page 1C-1).

Replace the FP relay 
with a new one.

1

I947H1110070-01

1A-100 Engine General Information and Diagnosis: 

P0230-H (Use of SDS)

P0230-L (Use of SDS)

Step

Action

Yes

No

1

1) Turn the ignition switch OFF.

2) Remove the frame covers. Refer to “Exterior Parts 

Removal and Installation” in Section 9D (Page 9D-6).

3) Check the FP relay coupler (1) for loose or poor 

contacts.
If OK, then check the FP relay. Refer to “Fuel Pump 
Relay Inspection” in Section 1G (Page 1G-7).

Is the FP relay OK?

• Y/B wire shorted to 

power source.

• Y/B wire shorted to 

ground.

• If wire and 

connection are OK, 
intermittent trouble or 
faulty ECM.

• Recheck each 

terminal and wire 
harness for open 
circuit and poor 
connection.

• Replace the ECM 

with a known good 
one, and inspect it 
again. Refer to “ECM 
Removal and 
Installation” in 
Section 1C 
(Page 1C-1).

Replace the FP relay 
with a new one.

1

I947H1110071-01

Step

Action

Yes

No

1

1) Turn the ignition switch OFF.

2) Remove the frame covers. Refer to “Exterior Parts 

Removal and Installation” in Section 9D (Page 9D-6).

3) Check the FP relay coupler (1) for loose or poor 

contacts.
If OK, then check the FP relay. Refer to “Fuel Pump 
Relay Inspection” in Section 1G (Page 1G-7).

Is the FP relay OK?

• Y/B wire open or poor 

“40” connection.

• O/W wire open or 

shorted to ground.

• R/Bl or Y/R wire open 

or shorted to ground, 
or poor “24” 
connection.

• If wire and 

connection are OK, 
intermittent trouble of 
faulty ECM.

• Recheck each 

terminal and wire 
harness for open 
circuit and poor 
connection.

• Replace the ECM 

with a known good 
one, and inspect it 
again. Refer to “ECM 
Removal and 
Installation” in 
Section 1C 
(Page 1C-1).

Replace the FP relay 
with a new one.

1

I947H1110072-01

Engine General Information and Diagnosis:  1A-101

DTC “C41” (P2505): ECM Power Input Signal Malfunction

B947H11104026

Detected Condition and Possible Cause

Wiring Diagram

ECM coupler (Harness side)

Troubleshooting

CAUTION

!

 

When using the multi-circuit tester, do not strongly touch the terminal of the ECM coupler with a 
needle pointed tester probe to prevent terminal damage.

 

NOTE

After repairing the trouble, clear the DTC using SDS tool. Refer to “Use of SDS Diagnosis Reset 
Procedures” (Page 1A-14).

 

Detected Condition

Possible Cause

C41/P2505

No voltage is applied to the ECM.

• Lead wire/coupler connection of ECM terminal to fuel 

fuse.

• Fuel fuse.

ECM

Side-stand
relay

Engine stop 
switch

Fuel pump  
relay

Fuel pump

Ignition  
switch

M

Y/R

VM

FP relay

R/BI

O/W

Y/B

To side-stand 
switch

24

BATT

10

40

R/Bl

To speedometer

I837H1110092-01

1

2

3

4

5

6

7

8

9 10 11 12

13 14 15 16 17 18 19 20 21 22 23 24

25 26 27 28 29 30 31 32 33 34 35 36

37 38 39 40 41 42 43 44 45 46 47 48

49 50 51 52 53 54 55 56 57 58 59 60

61 62 63 64 65 66 67 68 69 70 71 72

I837H1110007-02

1A-102 Engine General Information and Diagnosis: 

Step

Action

Yes

No

1

1) Turn the ignition switch OFF.

2) Remove the front seat. Refer to “Exterior Parts Removal 

and Installation” in Section 9D (Page 9D-6).

3) Check the ECM coupler for loose or poor contacts. If OK, 

then measure the ECM input voltage.

4) Disconnect the ECM coupler. Refer to “ECM Removal 

and Installation” in Section 1C (Page 1C-1).

5) Insert the needle pointed probe to ECM coupler.

6) Measure the voltage between terminal “10” and ground.

Special tool

(A):  09900–25008 (Multi circuit tester set)
(B):  09900–25009 (Needle-point probe set)

Tester knob indication
Voltage (

)

ECM input voltage
Battery voltage
((+) terminal: “10” – (–) terminal: Ground)

ECM couplers (Harness side)

Is the voltage OK?

• Fuel pump relay 

circuit malfunction.

Refer to “DTC “C41” 
(P0230-H/L): FP 
Relay Circuit 
Malfunction” 
(Page 1A-98).

• R/Bl wire open or 

short or poor “10” 
connection.

• Power source of 

speedometer shorted 
to the grand or open.

• If wire and 

connection are OK, 
intermittent trouble or 
faulty ECM.

• Recheck each 

terminal and wire 
harness for open 
circuit and poor 
connection.

• Replace the ECM 

with a known good 
one, and inspect it 
again. Refer to “ECM 
Removal and 
Installation” in 
Section 1C 
(Page 1C-1).

Open or short circuit in 
the R/Bl wire.

I947H1110073-01

“10”

(A)

(B)

I837H1110093-01

Engine General Information and Diagnosis:  1A-103

DTC “C42” (P1650): IG Switch Circuit Malfunction

B947H11104027

Detected Condition and Possible Cause

Troubleshooting

NOTE

• Refer to “Ignition Switch Inspection” in Section 9C (Page 9C-7) for details.

• After repairing the trouble, clear the DTC using SDS tool. Refer to “Use of SDS Diagnosis Reset 

Procedures” (Page 1A-14).

 

DTC “C44” (P0130/P0135): HO2 Sensor (HO2S) Circuit Malfunction

B947H11104028

Detected Condition and Possible Cause

Wiring Diagram

ECM coupler (Harness side)

Detected Condition

Possible Cause

Ignition switch signal is not input to the ECM.

• Ignition system circuit open or short.

• ECM malfunction.

When the ID agreement is not verified.
ECM does not receive communication signal from the 
immobilizer antenna.
(For E-02, 19, 24, 51)

• Immobilizer system malfunction.

(For E-02, 19, 24, 51)

Detected Condition

Possible Cause

C44/P0130

HO2 sensor output voltage is not input to 
ECM during engine operation and running 
condition.
Sensor voltage > 1.0 V

• HO2 sensor circuit is open or shorted to the power 

source.

C44/P0135

The heater can not operate so that heater 
operation voltage is not supplied to the 
oxygen heater circuit.

• Heated circuit is open or shorted to ground.

• Battery voltage is not supply to the HO2 sensor.

ECM

Side-stand  
relay

Ignition  
switch

Engine stop  
switch

O/W

W

Gr

B

W

B/Br

W/G

W/B

HO2 sensor

HO2S

HO2SH

E2

To Side-stand 
switch

34

41

35

I837H1110094-01

1

2

3

4

5

6

7

8

9 10 11 12

13 14 15 16 17 18 19 20 21 22 23 24

25 26 27 28 29 30 31 32 33 34 35 36

37 38 39 40 41 42 43 44 45 46 47 48

49 50 51 52 53 54 55 56 57 58 59 60

61 62 63 64 65 66 67 68 69 70 71 72

I837H1110007-02

1A-104 Engine General Information and Diagnosis: 

Troubleshooting (When Indicating C44/P0130:)

CAUTION

!

 

When using the multi-circuit tester, do not strongly touch the terminal of the ECM coupler with a 
needle pointed tester probe to prevent terminal damage.

 

NOTE

After repairing the trouble, clear the DTC using SDS tool. Refer to “Use of SDS Diagnosis Reset 
Procedures” (Page 1A-14).

 

Step

Action

Yes

No

1

1) Turn the ignition switch OFF.

2) Lift and support the fuel tank. Refer to “Fuel Tank 

Removal and Installation” in Section 1G (Page 1G-9).

3) Check the HO2 sensor coupler (1) for loose or poor 

contacts.
If OK, then check the HO2 sensor lead wire continuity.

4) Disconnect the HO2 sensor coupler.

5) Check the continuity between the W/G wire and O/W 

wire. If the sound is not heard from the tester, the circuit 
condition is OK.

Special tool

(A):  09900–25008 (Multi circuit tester set)

Tester knob indication
Continuity test (

)

Go to Step 2.

W/G wire shorted to the 
power source, or W/G 
or B/Br wire open.

1

I947H1110074-01

(A)

I947H1110075-01

Engine General Information and Diagnosis:  1A-105

Step

Action

Yes

No

1

6) Disconnect the ECM coupler. Refer to “ECM Removal 

and Installation” in Section 1C (Page 1C-1).

7) Check the continuity between the W/G wire and terminal 

“34”. Also, check the continuity between the B/Br wire 
and terminal “35”.

Special tool

(A):  09900–25008 (Multi circuit tester set)
(B):  09900–25009 (Needle-point probe set)

Tester knob indication
Continuity (

)

ECM couplers (Harness side)

Is the continuity OK?

Go to Step 2.

W/G wire shorted to the 
power source, or W/G 
or B/Br wire open.

(Black)

(Gray)

?

(A)

(B)

“34”

“35”

I837H1110095-01

1A-106 Engine General Information and Diagnosis: 

2

1) Connect the ECM coupler and HO2 sensor coupler.

2) Warm up the engine enough.

3) Insert the needle pointed probes to the lead wire coupler.

4) Measure the HO2 sensor output voltage between the W/

G (B) wire and B/Br (Gr) wire, in idling condition.

Special tool

(A):  09900–25008 (Multi circuit tester set)
(B):  09900–25009 (Needle-point probe set)

Tester knob indication
Voltage (

)

HO2 sensor output voltage at idle speed
0.3 V and less
((+) terminal: W/G (B) – (–) terminal: B/Br (Gr))

5) If OK, then remove the air cleaner box and pinch the 

PAIR hose (1) with a proper hose clamp.

6) Measure the HO2 sensor output voltage while holding 

the engine speed at 5 000 r/min.

HO2 sensor output voltage at 5 000 r/min
0.6 V and more
((+) terminal: W/G – (–) terminal: B/Br)

Is the voltage OK?

• W/G or B/Br wire 

open or shorted to 
the power source, or 
poor “34” or “35” 
connection.

• If wire and 

connection are OK, 
intermittent trouble or 
faulty ECM.

• Recheck each 

terminal and wire 
harness for open 
circuit and poor 
connection.

• Replace the ECM 

with a known good 
one, and inspection it 
again. Refer to “ECM 
Removal and 
Installation” in 
Section 1C 
(Page 1C-1).

Replace the HO2 
sensor with a new one. 
Refer to “HO2 Sensor 
Removal and 
Installation” in Section 
1C (Page 1C-8).

Step

Action

Yes

No

(A)

(B)

I947H1110076-01

1

I947H1110077-01

Engine General Information and Diagnosis:  1A-107

Troubleshooting (When Indicating C44/P0135:)

NOTE

After repairing the trouble, clear the DTC using SDS tool. Refer to “Use of SDS Diagnosis Reset 
Procedures” (Page 1A-14).

 

Step

Action

Yes

No

1

1) Turn the ignition switch OFF.

2) Lift and support the fuel tank. Refer to “Fuel Tank 

Removal and Installation” in Section 1G (Page 1G-9).

3) Check the HO2 sensor coupler (1) for loose or poor 

contacts.
If OK, then measure the HO2 sensor resistance.

4) Disconnect the HO2 sensor coupler and measure the 

resistance between terminals.

CAUTION

!

 

• Temperature of the sensor affects resistance 

value largely.

• Make sure that the sensor heater is in 

atmospheric temperature.

 

Special tool

(A):  09900–25008 (Multi circuit tester set)

Tester knob indication
Resistance (

Ω

)

HO2 sensor heater resistance
6.7 – 9.5 

Ω

 at 23 

°

C (73 

°

F)

(W – W)

Is the resistance OK?

Go to Step 2.

Replace the HO2 
sensor with a new one. 
Refer to “HO2 Sensor 
Removal and 
Installation” in Section 
1C (Page 1C-8).

1

I947H1110078-01

(A)

I947H1110079-01

1A-108 Engine General Information and Diagnosis: 

2

1) Connect the HO2 sensor coupler.

2) Insert the needle pointed probes to the lead wire coupler.

3) Turn the ignition switch ON and measure the heater 

voltage between the W/B wire and ground.
If the tester voltage indicates the battery voltage, it is 
good condition.

NOTE

Battery voltage can be detected only before 
starting the engine.

 

Special tool

(A):  09900–25008 (Multi circuit tester set)
(B):  09900–25009 (Needle-point probe set)

Tester knob indication
Voltage (

)

Heater voltage
Battery voltage
((+) terminal: W/B – (–) terminal: Ground)

Is the voltage OK?

• O/W or W/B wire 

open or shorted to 
ground, or poor “41” 
connection.

• Recheck each 

terminal and wire 
harness for open 
circuit and poor 
connection.

• If wire and 

connection are OK, 
intermittent trouble or 
faulty ECM.

• Replace the ECM 

with a known good 
one, and inspect it 
again. Refer to “ECM 
Removal and 
Installation” in 
Section 1C 
(Page 1C-1).

• Open or short circuit 

in the W/B wire or O/
W wire.

• Loose or poor 

contacts on the ECM 
coupler or HO2 
sensor coupler.

Step

Action

Yes

No

(A)

(B)

I947H1110080-01

Engine General Information and Diagnosis:  1A-109

DTC “C46” (P1657-H/L or P1658): EXCV Actuator Circuit Malfunction

B947H11104029

Wiring Diagram

ECM coupler (Harness side)

Troubleshooting

CAUTION

!

 

When using the multi-circuit tester, do not strongly touch the terminal of the ECM coupler with a 
needle pointed tester probe to prevent terminal damage.

 

NOTE

After repairing the trouble, clear the DTC using SDS tool. Refer to “Use of SDS Diagnosis Reset 
Procedures” (Page 1A-14).

 

Detected Condition

Possible Cause

C46

The operation signal does not reach the 
EXCV actuator.
EXCVA position sensor voltage low or 
high
0.14 V 

≤

 Sensor voltage < 4.9 V

(without the above range) 
EXCVA can not operate properly.

• EXCVA maladjusted.

• EXCVA circuit open or short.

• EXCVA motor malfunction.

• EXCVA position sensor malfunction.

• EXCVA position sensor circuit shorted to VCC or ground 

circuit open.

• EXCVA position sensor circuit open or shorted to ground 

or VCC circuit open.

• EXCVA motor circuit open or short.

• EXCVA motor malfunction.

P1657

H

Sensor voltage is higher than specified 
value.

L

Sensor voltage is lower than specified 
value.

P1658

The operation signal does not reach the 
EXCVA motor.
EXCVA can not operate properly.

ECM

EXCVA

VCC

EXCVAS

EXCVA

EXCVA

E2

B/R

R/B

P

Gr

B/Br

W

Y

Y

R

B

1

13

7

14

35

I947H1110081-01

1

2

3

4

5

6

7

8

9 10 11 12

13 14 15 16 17 18 19 20 21 22 23 24

25 26 27 28 29 30 31 32 33 34 35 36

37 38 39 40 41 42 43 44 45 46 47 48

49 50 51 52 53 54 55 56 57 58 59 60

61 62 63 64 65 66 67 68 69 70 71 72

I837H1110007-02

1A-110 Engine General Information and Diagnosis: 

C46 (Use of mode select switch)

Step

Action

Yes

No

1

1) Turn the ignition switch OFF.

2) Remove the left side cowling. Refer to “Exterior Parts 

Removal and Installation” in Section 9D (Page 9D-6).

3) Check the EXCVA coupler (1) for loose or poor contacts.

4) Turn the ignition switch ON.

5) Check the operation of the EXCVA.

(EXCVA operation order: Full close 

→

 Full open 

→

 

Approx. 80% open)

Is the operation OK?

Go to Step 2.

Go to Step 6.

1

I947H1110082-01

I947H1110083-01

Engine General Information and Diagnosis:  1A-111

P1657-H (Use of SDS)

Step

Action

Yes

No

1

1) Turn the ignition switch OFF.

2) Remove the left side cowling. Refer to “Exterior Parts 

Removal and Installation” in Section 9D (Page 9D-6).

3) Check the EXCVA coupler (1) for loose or poor contacts.

If OK, then check the EXCVA position sensor lead wire 
continuity.

4) Disconnect the EXCVA coupler.

5) Check the continuity between R wire and Y wire.

If the sound is not heard from the tester, the circuit 
condition is OK.

Special tool

(A):  09900–25008 (Multi circuit tester set)

Tester knob indication
Continuity (

)

6) Disconnect the ECM couplers.

7) Check the continuity between Y wire and terminal “14”.

Go to Step 4.

Y wire shorted to VCC, 
or B/Br wire open.

1

I947H1110084-01

?

(A)

I947H1110085-01

1A-112 Engine General Information and Diagnosis: 

Step

Action

Yes

No

1

8) Also, check the continuity between B/Br wire and 

terminal “35”.

Special tool

(A):  09900–25008 (Multi circuit tester set)
(B):  09900–25009 (Needle-point probe set)

Tester knob indication
Continuity (

)

EXCVA lead wire continuity
Continuity (

)

ECM couplers (Harness side)

Is the continuity OK?

Go to Step 4.

Y wire shorted to VCC, 
or B/Br wire open.

(Black)

(Gray)

?

(A)

“14”

“35”

(B)

I947H1110086-01

Engine General Information and Diagnosis:  1A-113

P1657-L (Use of SDS)

Step

Action

Yes

No

1

1) Turn the ignition switch OFF.

2) Remove the left side cowling. Refer to “Exterior Parts 

Removal and Installation” in Section 9D (Page 9D-6).

3) Check the EXCVA coupler (1) for loose or poor contacts.

If OK, then check the EXCVA position sensor lead wire 
continuity.

4) Disconnect the EXCVA coupler.

5) Check the continuity between Y wire and ground.

6) Also, check the continuity between Y wire and B/Br wire. 

If the sound is not heard from the tester, the circuit 
condition is OK.

Special tool

(A):  09900–25008 (Multi circuit tester set)

Tester knob indication
Voltage (

)

7) Disconnect the ECM coupler.

8) Check the continuity between Y wire and terminal “14”.

Go to Step 2 and go to 
Step 4.

R or Y wire open, or Y 
wire shorted to ground.

1

I947H1110087-01

?

(A)

I947H1110088-01