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 alternating current (AC) voltage signal whose frequency is proportional to the wheel speed. The magnitude of this signal is directly related to wheel speed and the proximity of the wheel speed sensor to the toothed ring often referred to as the air gap.
Conditions for Running the DTC
This test detects a short to battery, ground, or open in the left rear wheel speed sensor circuit.
Conditions for Setting the DTC
| • | The wheel speed circuit is open or shorted to the battery or ground. |
| • | There is a loose connection in the wheel speed circuit. |
| • | The wheel speed sensor resistance is very high. |
| • | The electronic brake control module (EBCM) is malfunctioning. |
Action Taken When the DTC Sets
This is a critical operational fault. The antilock brake system (ABS) is disabled and the ABS warning lamp is turned ON. The proportioning is operation.
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.
The following are possible causes of the malfunction:
| • | A short to ground or a short to voltage in the wheel speed sensor circuitry |
| • | An open or high resistance in the wheel speed sensor circuitry |
| • | A malfunctioning wheel speed sensor |
| • | A malfunctioning wheel speed sensor rotor |
| • | An internal EBCM malfunction |
If an intermittent malfunction exists, refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: Antilock Brake System Schematics Connector End View Reference: Antilock Brake System Connector End Views | ||||
1 |
Is the resistance within the specified value? | 1.0-1.5 kohms | Go to Step 4 | Go to Step 2 |
2 |
Is the resistance within the specified value? | 1.0-1.5 kohms | Go to Step 4 | Go to Step 3 |
3 | Replace the wheel speed sensor. Is the repair complete? | -- | System OK | -- |
4 |
Does the DVM show the specified value? | less than 1 ohms | Go to Step 6 | Go to Step 5 |
5 | Repair the high resistance between terminal 7 of the connector C202 and terminal 22 of the EBCM connector. Is the repair complete? | -- | System OK | -- |
6 | Use a DVM to measure the resistance between terminal 7 of the connector C202 and terminal 2 of the left rear wheel speed sensor harness connector. Is the resistance within the specified value? | less than 1 ohms | Go to Step 8 | Go to Step 7 |
7 | Repair the high resistance between terminal 7 of the connector C202 and terminal 2 of the left rear wheel speed sensor harness connector. Is the repair complete? | -- | System OK | -- |
8 | Use a DVM to measure the resistance between terminal 14 of the connector C202 and terminal 23 of the EBCM connector. Does the DVM show the specified value? | less than 1 ohms | Go to Step 10 | Go to Step 9 |
9 | Repair the high resistance between terminal 14 of the connector C202 and terminal 23 of the EBCM connector. Is the repair complete? | -- | System OK | -- |
10 | Use a DVM to measure the resistance between terminal 14 of the connector C202 and terminal 1 of the left rear wheel speed sensor harness connector. Is the resistance within specified value? | less than 1 ohms | Go to Step 12 | Go to Step 11 |
11 | Repair the high resistance between terminal 14 of the connector C202 and terminal 1 of the left rear wheel speed sensor harness connector. Is the repair complete? | -- | System OK | -- |
12 | Use a DVM to measure the resistance between ground and terminal 22 of the EBCM connector. Does the DVM show the specified value? | ∞ | Go to Step 14 | Go to Step 13 |
13 | Repair the short to ground between terminal 7 of the connector C202 and terminal 22 of the EBCM connector. Is the repair complete? | -- | System OK | -- |
14 | Use a DVM to measure the resistance between ground and terminal 7 of the connector C202. Does the DVM show the specified value? | ∞ | Go to Step 16 | Go to Step 15 |
15 | Repair the short to ground between terminal 7 of the connector C202 and terminal 2 of the left rear wheel speed sensor harness connector. Is the repair complete? | -- | System OK | -- |
16 | Use a DVM to measure the resistance between ground and terminal 23 of the EBCM connector. Does the DVM show the specified value? | ∞ | Go to Step 18 | Go to Step 17 |
17 | Repair the short to ground between terminal 14 of the connector C202 and terminal 23 of the EBCM connector. Is the repair complete? | -- | System OK | -- |
18 | Use a DVM to measure the resistance between ground and terminal 14 of the connector C202. Does the DVM show the specified value? | ∞ | Go to Step 20 | Go to Step 19 |
19 | Repair the short to ground between terminal 14 of the connector C202 and terminal 1 of the left rear wheel speed sensor harness connector. Is the repair complete? | -- | System OK | -- |
20 |
Is the voltage within the specified value? | 0 V | Go to Step 22 | Go to Step 21 |
21 | Repair the short to voltage between terminal 7 of the connector C202 and terminal 22 of the EBCM connector. Is the repair complete? | -- | System OK | -- |
22 |
Is the voltage within the specified value? | 0 V | Go to Step 24 | Go to Step 23 |
23 | Repair the short to voltage between terminal 7 of the connector C202 and terminal 2 of the left rear wheel speed sensor harness connector. Is the repair complete? | -- | System OK | -- |
24 |
Is the voltage within the specified value? | 0 V | Go to Step 26 | Go to Step 25 |
25 | Repair the short to voltage between terminal 14 of the connector C202 and terminal 23 of the EBCM connector. Is the repair complete? | -- | System OK | -- |
26 |
Is the voltage within the specified value? | 0 V | Go to Step 28 | Go to Step 27 |
27 | Repair the short to voltage between terminal 14 of the connector C202 and terminal 1 of the left rear wheel speed sensor harness connector. Is the repair complete? | -- | System OK | -- |
28 | Replace the EBCM. Is the repair complete? | -- | System OK | -- |
