Suzuki GSX-R 1000 Service Manual: DTC “c91” (p0500): vehicle speed sensor circuit malfunction

Suzuki GSX-R 1000 Service Manual / Engine / Engine general information and diagnosis / Diagnostic information and procedures / DTC “c91” (p0500): vehicle speed sensor circuit malfunction

Detected condition and possible cause

Detected condition

Possible cause

Speedometer does not receive signal from the vehicle speed sensor for more than 6 sec. When the motorcycle is running. Ecm does not receive signal from the vehicle speed sensor for more than 6 sec. When the motorcycle is running. Failure in communication between ecm and speedometer with reference to vehicle speed.

Speed sensor circuit open or short.
Speed sensor malfunction.
Speedometer malfunction.
Ecm malfunction.

Wiring diagram

Suzuki GSX-R. Wiring diagram

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” .

Step

Action

Yes

Turn the ignition switch off.
Lift and support the fuel tank. Refer to “fuel tank removal and installation” in section 1g .
Check the speed sensor coupler (1) for loose or poor contacts.

If ok, remove the speed sensor. Refer to “speed sensor removal and installation” in section 9c .

Connect 12 v battery, 10 kΩ resistor and the multi-circuit tester as shown in the figure.

Special tool
(a): 09900–25008 (multi
circuit tester set)

Tester knob indication voltage ( )

Under this condition, if a suitable screwdriver touching the pick-up surface of the speed sensor is moved, the tester reading voltage changes (0 v → 12 v or 12 v → 0 v). If the tester reading voltage does not change, replace the speedometer sensor with a new one.

Note

while testing, the highest voltage reading should be the same as the battery voltage (12 v).

Is the voltage ok?

P wire open or shorted to ground.
Loose or poor contacts on the speed sensor coupler or ecm coupler (terminal “2”).
If wires 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.

Inspect that metal particles or foreign material stuck on the speed sensor and rotor tip.
If there are no metal particles and foreign material, then replace the speed sensor with a new one.

DTC “c62” (p0443): evap system purge control solenoid valve circuit malfunction (e-33 only)

Detected condition and possible cause Detected condition Possible cause Evap system purge control valve voltage is not input to ecm. Evap system purge contro ...

DTC “c93” (p1769): steering damper solenoid valve circuit malfunction

Detected condition and possible cause Detected condition Possible cause C93 Steering damper control current does not flow to the solenoid valve. With ig turned on ...

Other materials:

Rear shock absorber removal and installation
Removal Remove the right side cowling and side frame covers. Refer to “exterior parts removal and installation” in section 9d . Support the motorcycle with a jack to relieve load on the rear shock absorber. Remove the left muffler and muffler chamber heat guard no. 2. Refer ...

Crankcase breather (pcv) hose inspection
Inspect the crankcase breather (pcv) hose in the following procedures: lift and support the fuel tank with the prop stay. Refer to “fuel tank removal and installation” in section 1g . Inspect the crankcase breather (pcv) hose (1) for wear and damage. If it is worn or damaged ...

Ap sensor removal and installation
Removal Remove the front seat. Refer to “exterior parts removal and installation” in section 9d (page 9d- 6). Disconnect the starter relay (1) from the holder. Disconnect the coupler (2) and remove the ap sensor (3). Installation Install the ap sensor in the rever ...