C1371

C1371
Wheel Sensor Front Left. Signal Incorrect

Fault symptoms
ABS warning lamp on. ABS not functioning.

Conditions
^ Speed signal absent for more than 10 ms when road speed above 40 km/h.
^ Speed signal faulty when road speed above 12 km/h.

Diagnostic help
^ FL wheel speed sensor signal can be read using diagnostic tool.
- Select "Read Values".
- Select " Wheel Speed Front Left".

The current wheel speed in km/h is displayed.
^ With the front of the car raised off the ground, the diagnostic tool should show a reading of about 5 km/h when the FL wheel is rotated by hand at a speed of about one turn a second.

Diagnostic procedure
1. Checking Wheel Speed





^ Contact ABS.





Drive the car at a steady speed.
Go to step 2

2. Checking Wheel Speed

Part 2 Of 2:

Part 2 Of 2:

^ Read value Wheel Speed Front Left (ABS).

Is the displayed FL wheel speed correct?

NO
Go to step 3

YES
go to step 7

3. Checking Mechanical Quantities





Check that the tire pressure, wheel size, wheel-bearing play and toothed wheel are OK.

Is the function correct?

NO
Go to step 4

YES
go to step 5

4. Checking Mechanical Quantities

Rectify the fault.

When repair is complete.
Go to step 7

5. Checking The Toothed Wheel Air Gap




The air gap between the toothed wheel and the sensor should be 0.3 - 1.3 mm.

Is the function correct?

NO
Go to step 6

YES
go to step 7

6. Checking The Toothed Wheel Air Gap

Rectify the fault.

When repair is complete.
Go to step 7.

7. Final Check





^ Clear the diagnostic trouble codes in all systems.





Carry out a drive cycle:

^ Drive the car at varying engine loads and engine rpm for five minutes.

Evaluate the drive cycle





^ Check that the diagnostic trouble code has not recurred

Is the function correct?

NO
Go to step 9

YES
go to step 8

8. Final Check

The steps taken to rectify the fault were correct.
Diagnosis is complete


9. Final Check

Diagnosis for this fault code is complete.
Refer to "Before Changing A Control Module" at General.