C1014
C1014 - Left Front Wheel Speed Comparative Performance
For a complete wiring diagram, refer to.
• When Monitored: With the ignition ON.
• Set Condition: When the left front wheel speed sensor signal reading is different from the readings received from the other WSS at a vehicle speed more than 40 km/h (25 m.p.h.). The anti lock brake module compares WSS readings from side-to-side on an axle and front-to-rear.
Test Step 1 - Test for DTC C1014 - Left Front Wheel Speed Comparative Performance
• This DTC must be active for the results of this test to be valid.
• Turn the ignition ON.
• With the scan tool, record and erase DTCs.
Ensure brake capability is available before road testing.
• Road test the vehicle over 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 met.
• With the scan tool, read DTCs.
Does the scan tool display C1014 - Left Front Wheel Speed Comparative Performance active?
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
• The condition that caused the symptom is currently not present. Inspect the related wiring for a possible intermittent condition. Look for any chafed, pierced, pinched, or partially broken wires.
• Perform the ABS Intermittent Condition Test. Refer to => Non-DTC Based Diagnostics. 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 Left Front WSS Looseness, Inspect Circuits/Terminals
for Damage ]
Test Step 4 - Test Left Front WSS Looseness, Inspect Circuits/Terminals for Damage
• Test all terminals for broken, bent, pushed out, or corroded terminals
• Inspect the anti lock brake module harness connector, left front WSS, and left front WSS harness connector.
• Inspect the left front WSS for looseness, excessive corrosion and not properly fastened.
• Inspect the left front WSS signal and B9 left front WSS supply circuits between the left front WSS and anti lock brake module for damage.
Is the left front WSS loose or any of the wiring/connectors/terminals damaged?
Yes
• Repair as necessary.
• Perform ABS Verification Test. Refer to => Non-DTC
Based Diagnostics. ABS Verification Test
No
• Go to Test Step 5 => [ Test Step 5 - Test Left Front Wheel Speed Sensor for Damage ]
Test Step 5 - Test Left Front Wheel Speed Sensor for Damage
• Remove the left front wheel speed sensor
• Inspect the left front wheel speed sensor face for damage.
Is the left front wheel speed sensor damaged?
Yes
• Replace sensor and hub assembly.
• Perform ABS Verification Test. Refer to => Non-DTC
Based Diagnostics. ABS Verification Test
No
• Go to Test Step 6 => [ Test Step 6 - Test Left Front Tone Wheel/Bearing for Damage ]
Test Step 6 - Test Left Front Tone Wheel/Bearing for Damage
• Inspect the left front tone wheel/bearing for damage, missing teeth, cracks, corrosion or looseness.
• The Tone Wheel teeth should be perfectly square, not bent, or nicked.
Is the left front tone wheel/bearing damaged?
Yes
• Repair as necessary.
• Perform ABS Verification Test. Refer to => Non-DTC
Based Diagnostics. ABS Verification Test
No
• Go to Test Step 7 => [ Test Step 7 - Left Front Wheel Speed Sensor ]
Test Step 7 - Left Front Wheel Speed Sensor
• Replace the left front wheel speed sensor.
• Perform ABS Verification Test. Refer to => Non-DTC
Based Diagnostics. ABS Verification Test
• Road test the vehicle over 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 met.
• With the scan tool, read ABS DTCs.
Did DTC C1014 - Left Front Wheel Speed Comparative Performance Reset?
Yes
• Replace the anti lock brake module.
• Perform ABS Verification Test. Refer to => Non-DTC
Based Diagnostics. ABS Verification Test
No
• Test Complete.