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 frequency of the AC voltage signal is proportional to the wheel speed. The amplitude of the AC voltage signal is directly related to wheel speed and the proximity of the wheel speed sensor to the toothed ring. The proximity of the wheel speed sensor to the toothed ring is also referred to as the air gap.
DTC C1232 can set anytime after initialization.
A malfunction exists if either of the left front wheel speed sensor circuits are open or shorted to voltage or ground.
• | A malfunction DTC stores. |
• | The ABS disables. |
• | The ABS warning indicator turns on. |
• | 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. |
The following conditions may cause an intermittent malfunction:
• | A poor connection |
• | Rubbed-through wire insulation |
• | A broken wire inside the insulation |
Use the enhanced diagnostic function of the Scan Tool in order to measure the frequency of the malfunction.
If the customer's comments reflect that the amber ABS warning indicator is on only during moist environmental changes (rain, snow, vehicle wash), inspect all the wheel speed sensor circuitry for signs of water intrusion. If the DTC is not current, clear all DTCs and simulate the effects of water intrusion by using the following procedure:
Add two teaspoons of salt to twelve ounces of water to make a five percent saltwater solution.
Thoroughly inspect any circuitry that may be causing the intermittent complaint for the following conditions:
• | Backed out terminals |
• | Improper mating |
• | Broken locks |
• | Improperly formed or damaged terminals |
• | Poor terminal-to-wiring connections |
• | Physical damage to the wiring harness |
Resistance of the wheel speed sensor will increase with an increase in sensor temperature.
Use the following procedure when replacing a wheel speed sensor or harness:
Step | Action | Value(s) | Yes | No | ||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Important: Zero the J 39200 test leads before making any resistance measurements. Refer to the J 39200 user's manual. Important: Difficulty may occur when trying to locate intermittent malfunctions in the wheel speed sensor circuit. Do not disturb any of the electrical connections. Change the electrical connections only when instructed to do so by a step in the diagnostic table. Changing the electrical connections at the correct time will ensure that an intermittent electrical connection will not be corrected until the source of the malfunction is found. | ||||||||||||||||||
1 | Was the Diagnostic System Check performed? | -- | Go to Diagnostic System Check | |||||||||||||||
2 |
Is the resistance within the specified range? | 1530-1870 ohms | ||||||||||||||||
3 | Use the J 39200 in order to measure the resistance between the EBCM harness connector terminal B4 and ground. Is the resistance within the specified range? | OL (Infinite) | ||||||||||||||||
4 |
Do not start the engine. Is the voltage within the specified range? | 0-1 V | ||||||||||||||||
5 |
Do not start the engine. Is the voltage within the specified range? | 0-1 V | ||||||||||||||||
6 | Use the J 39200 in order to measure the voltage between the EBCM harness connector B4 terminal A5 and ground. Is the voltage within the specified range? | 0-1 V | ||||||||||||||||
7 |
Are there signs of poor terminal contact, terminal corrosion, or damaged terminals? | -- | ||||||||||||||||
8 | Inspect the wiring of CKT 873 and CKT 830 for signs of wire damage. Wire damage may cause the following conditions in CKT 873 and CKT 830:
Are there signs of damaged wiring? | -- | ||||||||||||||||
9 | Inspect the harness connectors of CKT 873 and CKT 830 for signs of wire damage. Wire damage may cause the following conditions in CKT 873 and CKT 830:
Are there signs of damaged connectors? | -- | ||||||||||||||||
10 |
Does DTC C1232 set as a current DTC? | -- | ||||||||||||||||
11 |
Is the resistance within the specified range? | 0-2 ohms | ||||||||||||||||
12 | Use the J 39200 in order to measure the resistance between the EBCM connector terminal A5 and the left front wheel speed sensor harness connector terminal A. Is the resistance within the specified range? | 0-2 ohms | ||||||||||||||||
13 | Use the J 39200 in order to measure the resistance between the left front wheel speed sensor connector terminal A and the left front wheel speed sensor connector terminal B. Is the resistance within the specified range? | 1530-1870 ohms | ||||||||||||||||
14 |
Is the resistance within the specified range? | OL (Infinite) | ||||||||||||||||
15 | Use the J 39200 in order to measure the resistance between the EBCM connector terminal A5 and ground. Is the resistance within the specified range? | OL (Infinite) | ||||||||||||||||
16 |
Is the resistance within the specified range? | OL (Infinite) | ||||||||||||||||
17 | Use the J 39200 in order to measure the resistance between the left front wheel speed sensor harness connector terminal B and ground. Is the resistance within the specified range? | OL (Infinite) | ||||||||||||||||
18 | Use the J 39200 in order to measure the resistance between the left front wheel speed sensor connector terminal A and ground. Is the resistance within the specified range? | OL (Infinite) | ||||||||||||||||
19 | Repair the short to voltage in CKT 873. If the short to voltage is found in the left front wheel speed sensor harness, replace the left front wheel speed harness. Is the repair complete? | -- | Go to Diagnostic System Check | -- | ||||||||||||||
20 | Repair the short to voltage in CKT 830. If the short to voltage is found in the left front wheel speed sensor harness, replace the left front wheel speed harness. Is the repair complete? | -- | Go to Diagnostic System Check | -- | ||||||||||||||
21 | Repair the wiring damage in CKT 873 or CKT 830. If the wiring damage is found in the left front wheel speed sensor harness, replace the left front wheel speed jumper harness. Is the repair complete? | -- | Go to Diagnostic System Check | -- | ||||||||||||||
22 | Repair the connector damage in CKT 873 or CKT 830. If the connector damage is found in the left front wheel speed sensor harness, replace the left front wheel speed harness. Is the repair complete? | -- | Go to Diagnostic System Check | -- | ||||||||||||||
23 | Repair the open or high resistance in CKT 873. If the open or high resistance is found in the left front wheel speed sensor harness, replace the left front wheel speed sensor harness. Is the repair complete? | -- | Go to Diagnostic System Check | -- | ||||||||||||||
24 | Repair the open or high resistance in CKT 830. If the open or high resistance is found in the left front wheel speed sensor harness, replace the left front wheel speed harness. Is the repair complete? | -- | Go to Diagnostic System Check | -- | ||||||||||||||
25 | Repair the short to ground in CKT 873. If the short to ground is found in the left front wheel speed sensor harness, replace the left front wheel speed harness. Is the repair complete? | -- | Go to Diagnostic System Check | -- | ||||||||||||||
26 | Repair the short to ground in CKT 830. If the short to ground is found in the left front wheel speed sensor harness, replace the left front wheel speed harness. Is the repair complete? | -- | Go to Diagnostic System Check | -- | ||||||||||||||
27 | Replace all of the terminals and the connectors that exhibit signs of poor terminal contact, corrosion, or damaged terminals. Is the repair complete? | -- | Go to Diagnostic System Check | -- | ||||||||||||||
28 | Replace the left front wheel speed sensor. Refer to Wheel Speed Sensor Replacement . Is the repair complete? | -- | Go to Diagnostic System Check | -- | ||||||||||||||
29 | Replace the left front wheel speed sensor harness. Refer to Wheel Speed Sensor Jumper Harness Replacement . Is the repair complete? | -- | Go to Diagnostic System Check | -- | ||||||||||||||
30 | Replace the EBCM. Refer to Electronic Brake Control Module Replacement . Is the repair complete? | -- | Go to Diagnostic System Check | -- | ||||||||||||||
31 | The malfunction is intermittent or not present at this time. Inspect all of the connectors and the harnesses for damage that could cause the following conditions:
The sensor harness must be replaced if the sensor harness is damaged. Refer to Diagnostic Aids for more information. Is the action complete? | -- | System OK | -- |