Code No.C1210: Wheel Speed Sensor (RR) System (Open or Short to Earth or Power Supply)

caution

If there is any problem in the CAN bus lines, an incorrect diagnosis code may be set. Diagnose the CAN bus lines before the diagnosis codes (Refer to GROUP 54C, CAN bus-line diagnostic flow .)

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 ASTC-ECU.
  
• The hydraulic unit modulates the amount of braking force individually applied to each wheel cylinder.
  

DIAGNOSIS CODE SET CONDITIONS

PROBABLE CAUSES

• Malfunction of the wheel speed sensor
  
• Damaged wiring harness or connector
  
• Malfunction of the hydraulic unit (integrated with ASTC-ECU)
  

caution Before connecting or disconnecting the M.U.T.-III, turn the ignition switch to the "LOCK" (OFF) position. (1)Connect M.U.T.-III to the 16-pin diagnosis connector. (2)Turn the ignition switch to the "ON" position. (3)Diagnose the CAN bus line. (4)Turn the ignition switch to the "LOCK" (OFF) position. Q. Is the check result normal? Go to Step 3. Repair the CAN bus line (Refer to GROUP 54C, CAN bus line Diagnostic flow .) Then go to Step 2.

caution Before connecting or disconnecting the M.U.T.-III, turn the ignition switch to the "LOCK" (OFF) position. (1)Turn the ignition switch to the "ON" position. (2)Erase the diagnosis code. (3)Turn the ignition switch to the "LOCK" (OFF) position. (4)Turn the ignition switch to the "ON" position. (5)Check if the diagnosis code is set. (6)Turn the ignition switch to the "LOCK" (OFF) position. Q. Is code No.C1210 set? Go to Step 3. The procedure is complete.

(1) caution Before connecting or disconnecting the M.U.T.-III, turn the ignition switch to the "LOCK" (OFF) position. Connect M.U.T.-III to the 16-pin diagnosis connector. (2)Start the engine. (3)Set M.U.T.-III to the data reading mode, and check the data list item by driving the vehicle. Item 04: Rear right wheel speed sensor (4)Turn the ignition switch to the "LOCK" (OFF) position. Q. Does the speedometer indication match the M.U.T.-III indication? It can be assumed that this malfunction is intermittent. Refer to GROUP 00, How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction . Go to Step 4.

(1)Disconnect the connector A-48, and connect special tool ASC check harness (MB992159) to the wiring harness-side connector. note Do not connect special tool ASC check harness (MB992159) to the ASTC-ECU. (2)Measure the resistance between the ASTC-ECU connector terminal 12 and 28. Standard Value: 0.9 - 1.3 kΩ Q. Is the resistance between terminal 12 and 28 within the standard value? Go to Step 8. Go to Step 5.

Q. Is the check result normal? Go to Step 6. Repair or replace the damaged component(s). Then go to Step 8.

Check the rear right wheel speed sensor (Refer to ).

	Go to Step 8.

	Go to Step 7.

Q. Is the check result normal? Go to Step 8. Repair the wiring harness. Then go to Step 9.

Check again if the diagnosis code is set. (1)Turn the ignition switch to the "ON" position. (2)Erase the diagnosis code. (3)Turn the ignition switch to the "LOCK" (OFF) position. (4)Turn the ignition switch to the "ON" position. (5)Check if the diagnosis code is reset. (6)Turn the ignition switch to the "LOCK" (OFF) position. Q. Is code No.C1210 set? Replace the hydraulic unit assembly (integrated with ASTC-ECU). Then go to Step 9. It can be assumed that this malfunction is intermittent. Refer to GROUP 00, How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction .

(1)Turn the ignition switch to the "ON" position. (2)Erase the diagnosis code. (3)Turn the ignition switch to the "LOCK" (OFF) position. (4)Turn the ignition switch to the "ON" position. (5)Check if the diagnosis code is set. (6)Turn the ignition switch to the "LOCK" (OFF) position. Q. Is code No.C1210 set? Repeat the troubleshooting from Step 1. The procedure is complete.