DTC 11
DTC 11: Wheel Speed SensorPart 1 Of 2:
Part 2 Of 2:
CIRCUIT OPERATION
^ A toothed ABS rotor generates a voltage pulse as it moves across the pickup field of each wheel speed sensor.
^ The amount of voltage generated at each wheel is determined by the clearance between the ABS rotor teeth and the wheel speed sensor, and by the speed of rotation.
^ The wheel speed sensors transmit the frequency of the voltage pulses and the amount of voltage generated by each pulse to the ABS-ECU.
^ The ABS hydraulic unit modulates the amount of braking force individually applied to each wheel cylinder.
ABS DTC SET CONDITIONS
^ DTCs 11, 12, 13, 14 are output when signal is not input due to breakage of the wires of one or more of the four wheel-speed sensors. DTCs 21, 22, 23, 24 are output in the following cases:
^ Open circuit is not found but no input is received by one or more of the four wheel speed sensors at 10 km/h (6 mph) or more.
^ Sensor output drops due to a malfunctioning sensor or warped ABS rotor.
TROUBLESHOOTING HINTS (The most likely causes for these DTCs are to set are:)
DTC 11, 12, 13, 14
^ Malfunction of the wheel speed sensor
^ Damaged wiring harness or connector
^ Malfunction of the hydraulic unit (integrated with ABS-ECU)
DTC 21, 22, 23, 24
^ Malfunction of the wheel speed sensor
^ Damaged wiring harness or connector
^ Malfunction of the hydraulic unit (integrated with ABS-ECU)
^ Malfunction of the ABS rotor
^ Malfunction of the wheel bearing
^ Excessive clearance between the sensor and ABS rotor
DIAGNOSIS
Required Special Tools:
^ MB991223: Harness Set
^ MB991958: Scan Tool (MUT-III Sub Assembly)
^ MB991824: Vehicle Communication Interface
^ MB991827: MUT-III USB Cable
^ MB991911: MUT-III Main Harness B
^ MB991529: Diagnostic Trouble Code Check Harness
STEP 1. Check the wheel speed sensor installation.
Q: Is the wheel speed sensor bolted securely in place at the front knuckle or the rear knuckle?
YES: Go to Step 2.
NO: Install it properly and go to Step 9.
STEP 2. Check wheel speed sensor circuit at the ABS-ECU connector A-02.
1. Disconnect the connector A-02 and measure et the harness side.
2. Measure the resistance between the ABS-ECU connector terminals 1 and 3, 4 and 5, 6 and 7, or 8 and 9.
Standard Value: 1.28 - 1.92 k Ohms
Q: Is the resistance between terminals 1 and 3, 4 and 5, 6 and 7, or 8 and 9 within the standard value?
YES: Go to Step 6.
NO
NO
NO
STEP 3. Check the harness wires between the ABS-ECU connector A-02 (terminals 6 and 7) and the wheel speed sensor
NOTE: After inspecting the intermediate connector C-06, inspect the wires. If the intermediate connector C-06 is damaged, repair or replace it. If the connector has been repaired or replaced, go to Step 9.
Q: Is any of the harness wires between the ABS-ECU connector A-02 (terminals 6 and 7) and the wheel speed sensor
YES: Repair it and go to Step 9.
NO: Go to Step 7.
STEP 4. Check the harness wires between the ABS-ECU connector A-02 (terminals 4 and 5) and the wheel speed sensor
Q: Is any of the harness wires between the ABS-ECU connector A-02 (terminals 4 and 5) and the wheel speed sensor
YES: Repair it and then go to Step 9.
NO: Go to Step 7.
STEP 5. Check the harness wires between the ABS-ECU connector A-02 (terminals 1, 3, 8, and 9) and the wheel speed sensor connectors D-08
NOTE: After inspecting the intermediate connector C-90, C-94 or D- 16, inspect the wires. If the intermediate connector C-90, C-94 or D- 16 is damaged, repair or replace it. If the connector has been repaired or replaced, go to Step 9.
Q: Is any of the harness wires between the ABS-ECU connector A-02 (terminals 1, 3, 8, and 9) and the wheel speed sensor connectors D-08
YES: Repair it and then go to Step 9.
NO: Go to Step 7.
STEP 6. Check the wheel speed sensor output voltage. Refer to P.35B-46.
Output Voltage:
^ When measured with a voltmeter: 42 mV or more
^ When measured with oscilloscope (maximum voltage): 200 mV or more
Q: Does the voltage meet the specification?
YES: Replace the hydraulic unit (integrated with ABS-ECU) and then go to Step 9.
NO: Go to Step 7.
STEP 7. Check the wheel speed sensor or ABS rotor.
If there is a damage in any of the following check items, replace the wheel speed sensor or the ABS rotor.
Check items:
^ Wheel speed sensor internal resistance
Standard value: 1.28 ± 1.92 k Ohms
^ Insulation between the wheel speed sensor body and connector terminals
^ Toothed ABS rotor
Q: Is the wheel speed sensor or ABS rotor damaged?
YES: Replace the faulty part and then go to Step 9.
NO: Go to Step 8.
STEP 8. Check the wheel bearing.
Q: Is the wheel bearing damaged?
YES: Replace it and then go to Step 9.
NO: Go to Step 9.
STEP 9. Recheck for diagnostic trouble codes.
Q: Do the diagnostic trouble codes 11, 12, 13, 14, 21, 22, 23 or 24 reset?
YES: Go to Step 1.
NO: This diagnosis is complete.