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Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. 6:  This step tests the front wheel speed sensors for proper resistance value.
  2. 7:  This step tests the front wheel speed sensors for proper resistance value.
  3. 8:  This step tests the wheel speed sensor circuits for a short, open or high resistance.
DTC 28

Step Action Value(s) Yes No
Schematic Reference:  ABS Schematics  
Connector End View Reference:  ABS Connector End Views  
1 Did you perform A Diagnostic System Check - ABS? - Go to Step 2  Go to Diagnostic System Check - ABS 
2
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC reset?		 - Go to Step 3  Go to Diagnostic Aids
3 Inspect the wheel speed sensors for damage.
Is a wheel speed sensor damaged?		 - Go to Step 10  Go to Step 4 
4 Inspect the wheel speed sensor rings for damage.
Is a wheel speed sensor ring damaged?		 - Go to Step 11  Go to Step 5 
5
  1. Disconnect each front wheel speed sensor jumper harness connector at the main wiring harness.
  2. Measure the resistance across the terminals of the front wheel speed sensor side of the jumper harness.
Does the resistance measure within the specified range?		 1600-1800Ω Go to Step 7  Go to Step 6 
6 
  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Disconnect each front wheel speed sensor connector at the wheel speed sensor.
  3. Measure the resistance across the front wheel speed sensor terminals.
Does the resistance measure within the specified range?		 1600-1800Ω Go to Step 12  Go to Step 10 
7 
  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Disconnect the rear wheel speed sensor connectors.
  3. Measure the resistance across the rear wheel speed sensor terminals.
Does the resistance measure within the specified range?		 1444-1760Ω Go to Step 8  Go to Step 10 
8 
  1. Disconnect the EBCM harness connector.
  2. Test the wheel speed sensor circuits for the following:
    • An open
    • A short to ground
    • A short to voltage
    • Shorted together
Refer to Circuit Testing and Wiring Repairs in Wiring Systems.Did you find and correct the condition?		 - Go to Step 14  Go to Step 9 
9 Inspect for poor connections at the harness connector for the EBCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 14  Go to Step 13 
10 Replace the wheel speed sensor. Refer to Wheel Speed Sensor Replacement - Front  or Wheel Speed Sensor Replacement - Rear .
Did you complete the replacement?		 - Go to Step 14  -
11 Replace the wheel speed sensor ring. Refer to Wheel Bearing/Hub Replacement - Front in Front Suspension or Rear Axle Shaft Replacement in rear Drive Axle.
Did you complete the replacement?		 - Go to Step 14  -
12 Replace the front wheel speed sensor jumper harness. Refer to Wheel Speed Sensor Jumper Harness Replacement - Front (Left)  or Wheel Speed Sensor Jumper Harness Replacement - Front (Right) .
Did you complete the replacement?		 - Go to Step 14  -
13 Replace the electronic brake control module (EBCM). Refer to Electronic Brake Control Module Replacement .
Did you complete the replacement?		 - Go to Step 14  -
14
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC reset?		 - Go to Step 2  System OK
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