Circuit Description
As a toothed ring passes by the wheel speed sensor, changes in the electromagnetic field cause the wheel speed sensor to produce an AC voltage signal. The EBCM uses the frequency of the AC signal to calculate the wheel speed.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
The ignition switch is in the ON position and one of the follow occurs:
| • | A short to battery malfunction occurs if the high and low inputs are greater than 4.25 volts for 0.02 seconds. |
| • | A short to ground malfunction occurs if the high and low inputs are less than 0.75 volts for 0.02 seconds. |
| • | An open occurs if the high input is greater than 4.25 volts and the low input is less than 0.75 volts for 0.02 seconds. |
Action Taken When the DTC Sets
| • | The EBCM stores a malfunction DTC. |
| • | The EBCM disables the ABS and ETS. |
| • | The ABS warning indicator turns ON. |
| • | The TRAC OFF indicator turns ON. |
Conditions for Clearing the DTC
| • | The condition responsible for setting the DTC no longer exists and the Scan Tool Clear DTCs function is used. |
| • | 100 drive cycles pass with no DTCs detected. A drive cycle consists of starting the vehicle, driving the vehicle over 16 km/h (10 mph), stopping and then turning the ignition OFF. |
Diagnostic Aids
| • | Thoroughly inspect the wiring and the connectors. An incomplete inspection of the wiring and the connectors may result in a misdiagnosis, causing a part replacement with the reappearance of the malfunction. |
| • | Poor connections, broken insulation, or a break in the wire inside the insulation may cause an intermittent malfunction. |
| • | If an intermittent malfunction exists, refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. |
Test Description
The number below refers to the step number on the diagnostic table.
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This step tests the wheel speed sensor and the wheel speed sensor signal circuits for an open.
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This step tests the wheel speed sensor and the wheel speed sensor signal circuits for a short to ground.
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This step tests the wheel speed sensor and the wheel speed sensor signal circuits for a short to voltage.
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This step tests the wheel speed sensor for the proper resistance value.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the ABS Diagnostic System Check? | -- | Go to Step 2 | |
Does the resistance measure within the specified range? | 1530-1870 ohms | Go to Step 3 | Go to Step 5 | |
Test the wheel speed sensor circuit, at the J 39700 universal pinout box, for a short to ground. Is a short to ground present? | -- | Go to Step 8 | Go to Step 4 | |
Is a short to voltage present? | -- | Go to Step 11 | Go to Step 13 | |
Does the resistance measure within the specified range? | 1530-1870 ohms | Go to Step 6 | Go to Step 15 | |
6 | Test the wheel speed sensor signal low circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 17 | Go to Step 7 |
7 | Test the wheel speed sensor signal high circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 17 | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems |
8 |
Is the wheel speed sensor internally shorted to ground? | -- | Go to Step 15 | Go to Step 9 |
9 | Test the wheel speed sensor signal low circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 17 | Go to Step 10 |
10 | Test the wheel speed sensor signal high circuit for a short to ground. Refer to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 17 | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems |
11 |
Did you find and correct the condition? | -- | Go to Step 17 | Go to Step 12 |
12 | Test the wheel speed sensor signal high circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 17 | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems |
13 | Inspect for poor connections/terminal tension at the wheel speed sensor harness connector. 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 17 | Go to Step 14 |
14 | Inspect for poor connections/terminal tension at the EBCM harness connector. 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 17 | Go to Step 16 |
15 | Replace the wheel speed sensor. Refer to Front Wheel Speed Sensor Replacement . Did you complete the repair? | -- | Go to Step 17 | -- |
16 | Replace the EBCM. Refer to Electronic Brake Control Module Replacement . Did you complete the repair? | -- | Go to Step 17 | -- |
17 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
