C1041

C1041 - Left Front Tone Wheel Performance

For a complete wiring diagram, refer to.

• When Monitored: With the ignition ON.

• Set Condition: When the anti lock brake module detects periodic drops of a WSS signal.






Test Step 1 - Test for A DTC C1041-Left Front Tone Wheel Performance

• This DTC must be active for the results of this test to be valid. If DTC C100A Left Front Wheel Speed Sensor Circuit is present it must be repaired before continuing.

• Turn the ignition ON.

• With the scan tool, read DTCs.

• With the scan tool, read and record Environmental Data to help identify the conditions in which the DTC was set.

• With the scan tool, erase DTCs.

• Cycle the ignition switch OFF then ON.


Ensure brake capability is available before road testing.

• Test drive the vehicle in a straight line to 40 km/h (25 m.p.h.).

• Vehicle must be driven more than 40 km/h (25 m.p.h.) for set conditions to be meet.

• With the scan tool, read DTCs.

Does the scan tool display C1041 - Left Front Tone Wheel Performance?

Yes

• Go to Test Step 3 => [ Test Step 3 - Test for Improper Left Front Tire Pressure/Mismatched
Tires ]

No

• Go to Test Step 2 => [ Test Step 2 - Test Wheel Speed Sensor Signals ]

Test Step 2 - Test Wheel Speed Sensor Signals

• Turn the ignition ON.

• With the scan tool, monitor and graph ALL the WSS speeds and compare graph while an assistant drives the vehicle.

• If graph shows periodic dropouts pay close attention to the tone wheel.

• Slowly accelerate as straight as possible from a stop to 40 km/h (25 m.p.h.).

Is the left front WSS speed showing 0 km/h (0 m.p.h.) or not matching other wheels or showing erratic behavior?

Yes

• Go to Test Step 3 => [ Test Step 3 - Test for Improper Left Front Tire Pressure/Mismatched
Tires ]

No

• Perform the ABS Intermittent Condition Test. ABS Intermittent Condition Test

Test Step 3 - Test for Improper Left Front Tire Pressure/Mismatched Tires

• Turn the ignition OFF.

• Test and adjust the left front tire pressure.

• Test and adjust all other tire pressures.

• Inspect for mismatched tires on vehicle.

Is the Left Front Tire improperly inflated or mismatched tires on vehicle?

Yes

• Repair as necessary.

• Perform ABS Verification Test. Refer to => Non-DTC
Based Diagnostics. ABS Verification Test

No

• Go to Test Step 4 => [ Test Step 4 - Test the Left Front Tone Wheel/Bearing for Damage ]

Test Step 4 - Test the Left Front Tone Wheel/Bearing for Damage

• Test the tone wheel teeth for missing teeth, cracks, or looseness. Teeth should be perfectly square, not bent, or nicked.

• Test the left front tone wheel/bearing for damage.

• Test the left front tone wheel for dirt.

Was the tone wheel dirty?

Yes

• Clean tone wheel and sensor. Clear codes and retest.

• Perform ABS Verification Test. Refer to => Non-DTC
Based Diagnostics. ABS Verification Test

No

• Replace the left front tone wheel/bearing.

• Perform ABS Verification Test. Refer to => Non-DTC
Based Diagnostics. ABS Verification Test