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Home >> Ford >> 2000 >> Mustang Base, 2D Convertible, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 1319 (Anti-Lock Brake System - Vehicle Dynamic Systems) >> Diagnosis And Testing >> Anti-Lock Control >> Pinpoint Tests >> Pinpoint Test E: DTC C1233, DTC C1234, DTC C1235, DTC C1236 - Wheel Speed Sensor Input Signal Missing >> Overview
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Pinpoint Test E: DTC C1233, DTC C1234, DTC C1235, DTC C1236 - Wheel Speed Sensor Input Signal Missing: Overview

WARNING: This page is about a different car, the 2006 Mercury Mariner and 2006 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION: Use the flex probe kit for all test connections to prevent damage to the wiring terminals. Do not use standard multimeter probes.
  1. E1 CHECK THE DTCs FROM THE SELF-TEST 
    • Using the recorded results from the ABS self-test:
    • Are DTCs C1145, C1155, C1165 or C1175 present? 

    Yes:  GO to PINPOINT TEST D .

    No  : GO to  E2.

  2. E2 MONITOR THE WHEEL SPEED PIDs 
    • Connect the scan tool.
    • Key in ON position.
    • Enter the following diagnostic mode on the scan tool: ABS Module PIDs.
    • Use the diagnostic tool to monitor the ABS module wheel speed sensor PIDs while driving the vehicle at a constant speed.
    • Are all the wheel speed sensor PID values similar? 

    Yes:  CLEAR the DTCs. DRIVE the vehicle. RETRIEVE the DTCs. If DTCs C1233, C1234, C1235 or C1236 are present, GO to  E12.

    No:  If the active wheel speed sensor tool is available, GO to  E3. If the active wheel speed sensor tool is not available, GO to  E6.

  3. E3 CHECK THE ABS MODULE OUTPUT USING THE SPECIAL TOOL 
    • Key in OFF position.
    • Disconnect: Suspect Wheel Speed Sensor.
    • Connect the special tool to the wheel speed sensor connectors.
    • Key in ON position.
    • Select the correct system polarity on the special tool and turn the special tool power switch to the ON position.
    • Is the module output LED illuminated? 

    Yes:  GO to  E5.

    No:  GO to  E4.

  4. E4 CHECK THE WHEEL SPEED SENSOR CIRCUITS FOR AN OPEN 
    NOTE: Both circuits must be checked for each DTC.
    • Key in OFF position.
    • Disconnect: ABS Module C155.
    • Measure the resistance between ABS module C155, harness side and suspected wheel speed sensor connector, harness side, as follows:
      ABS MODULE CONNECTOR-PIN REFERENCE

      DTC Circuit ABS Module Connector-Pin Wheel Speed Sensor Connector-Pin
      C1233 521 (TN/OG) C155-45 LH front wheel speed sensor C150-2
      C1233 522 (TN/BK) C155-46 LH front wheel speed sensor C150-1
      C1234 514 (YE/RD) C155-34 RH front wheel speed sensor C160-2
      C1234 516 (YE/BK) C155-33 RH front wheel speed sensor C160-1
      C1235 524 (PK/BK) C155-42 RH rear wheel speed sensor C426-2
      C1235 523 (RD/PK) C155-43 RH rear wheel speed sensor C426-1
      C1236 518 (LG/RD) C155-36 LH rear wheel speed sensor C440-1
      C1236 519 (LG/BK) C155-37 LH rear wheel speed sensor C440-2
    • Are the resistances less than 5 ohms? 

    Yes:  GO to  E7.

    No:  REPAIR the circuit(s) in question. CLEAR the DTCs. REPEAT the self-test.

  5. E5 CHECK THE WHEEL SPEED SENSOR OUTPUT WITH THE SPECIAL TOOL 
    • Raise the suspect wheel until it can spin freely. Refer to JACKING & LIFTING .
    • While monitoring the special tool, slowly spin the suspect wheel.
    • Do the sensor output LEDs illuminate and flash and is the current overload LED not illuminated? 

    Yes:  INSPECT the wheel speed sensor tone ring for damage and looseness. INSTALL new components as necessary. If the tone ring is OK, the concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.

    No:  If the current level LED is not illuminated and the sensor output LEDs do not illuminate or if the current level LED is illuminated red, INSTALL a new wheel speed sensor. For the front wheel speed sensor, REFER to WHEEL SPEED SENSOR - FRONT . For the front wheel speed sensor, REFER to WHEEL SPEED SENSOR - REAR . CLEAR the DTCs. REPEAT the self-test. If the current level LED is not illuminated and the sensor output LEDs illuminate green but do not flash, INSPECT the wheel speed sensor tone ring and INSTALL new if necessary. If the tone ring is OK, INSTALL a new wheel speed sensor. For the front wheel speed sensor, REFER to WHEEL SPEED SENSOR - FRONT . For the front wheel speed sensor, REFER to WHEEL SPEED SENSOR - REAR . CLEAR the DTCs. REPEAT the self-test.

  6. E6 CHECK THE ABS MODULE OUTPUT 
    • Key in OFF position.
    • Disconnect: Suspect Wheel Speed Sensor.
    • Key in ON position.
    • Measure the voltage between the suspect wheel speed sensor pins, harness side.
      Fig 1: Checking ABS Module Output
      G04617721Courtesy of FORD MOTOR CO.
    • Is the voltage greater than 10 volts? 

    Yes:  INSTALL a new wheel speed sensor. REFER to WHEEL SPEED SENSOR - FRONT  or WHEEL SPEED SENSOR - REAR . CLEAR the DTCs. REPEAT the self-test.

    No:  GO to  E7.

  7. E7 INSPECT THE WHEEL SPEED SENSOR MOUNTING 
    • Key in OFF position.
    • With the vehicle in NEUTRAL, position it on a hoist. Refer to JACKING & LIFTING .
    • Inspect the wheel speed sensor mounting.
    • Is the wheel speed sensor loose? 

    Yes:  TIGHTEN the wheel speed sensor to specification. CLEAR the DTCs. GO to  E8.

    No:  GO to  E7.

  8. E8 RECHECK THE WHEEL SPEED PIDs 
    • Connect the scan tool.
    • Key in ON position.
    • Enter the following diagnostic mode on the scan tool: ABS Module PIDs.
    • Use the diagnostic tool to monitor the ABS module wheel speed sensor PIDs while driving the vehicle at a constant speed.
    • Are all the wheel speed sensor PID values similar? 

    Yes:  The vehicle is OK. The concern may have been caused by a loose wheel speed sensor.

    No:  GO to  E9.

  9. E9 CHECK THE WHEEL SPEED SENSOR FOR DAMAGE 
    • Key in OFF position.
      • CAUTION: Examine the wheel speed sensor wire carefully with a good light source. Failure to verify damage in the wheel speed sensor wire can lead to unnecessary installation of a new component.
    • Inspect the wheel speed sensor for damage.
    • Is the wheel speed sensor OK? 

    Yes:  GO to  E10.

    No:  INSTALL a new wheel speed sensor. REFER to WHEEL SPEED SENSOR - FRONT  or WHEEL SPEED SENSOR - REAR . CLEAR the DTCs. REPEAT the self-test.

  10. E10 CHECK FOR WHEEL SPEED SENSOR RING DAMAGE 
    • Remove the wheel speed sensor. Refer to WHEEL SPEED SENSOR - FRONT  or WHEEL SPEED SENSOR - REAR .
    • Inspect the wheel speed sensor ring for damaged or missing teeth. Rotate the wheel to verify that no teeth are missing.
    • Is the wheel speed sensor ring OK? 

    Yes:  GO to  E11.

    No:  If front, INSTALL a new front halfshaft. REFER to INSTALLATION . If rear and 4WD, INSTALL a new rear halfshaft. REFER to INSTALLATION . If rear and FWD, INSTALL a new wheel speed sensor ring. REFER to WHEEL SPEED SENSOR RING - REAR . CLEAR the DTCs. REPEAT the self-test.

  11. E11 CHECK FOR BEARING DAMAGE 
    • Inspect the wheel bearings for damage.
    • Are the wheel bearings OK? 

    Yes:  GO to  E12.

    No:  INSTALL a new wheel bearing as necessary. REFER to INSTALLATION for the front or INSTALLATION for the rear . CLEAR the DTCs. REPEAT the self-test.

  12. E12 CHECK FOR CORRECT ABS MODULE OPERATION 
    • Disconnect all the ABS connectors.
    • Check for:
      • corrosion.
      • pushed-out pins.
    • Connect all the ABS connectors and make sure they seat correctly.
    • Operate the system and verify the concern is still present.
    • Is the concern still present? 

    Yes:  INSPECT the wheel speed sensor tone ring for damage and looseness. INSTALL new components as necessary. If the tone ring is OK, INSTALL a new ABS module. REFER to ANTI-LOCK BRAKE SYSTEM (ABS) MODULE . TEST the system for normal operation.

    No:  The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.

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