C121A

C121A - Steering Angle Sensor Not Initialized






For a complete wiring diagram, refer to.

• When Monitored: With the ignition on.

• Set Condition: When the Anti-Lock Brake Module detects a low voltage at the Steering Angle Sensor or Steering Angle Sensor failure.






Test Step 1 - CHECK FOR A DTC C121A-STEERING ANGLE SENSOR NOT INITIALIZED

• This DTC must be active for the results of this test to be valid.

• Turn the ignition on.

• With the scan tool, read and record DTCs.

• With the scan tool, read and record Freeze Frame information.

• With the scan tool, erase DTCs.

• Test drive the vehicle by turning the vehicle left or right in a curving manner at a velocity between 10 and 25 km/hr (6 and 15 m.p.h.) for 1 minute.

• With the scan tool, read and record DTCs.

Does the scan tool display: C121A-STEERING ANGLE SENSOR NOT INITIALIZED?

Yes

• Go to Test Step 2 => [ Test Step 2 - CHECK THE TERMINALS/CONNECTORS/WIRING HARNESS FOR DAMAGE ]

No

• Perform the ABS Intermittent Condition Test. Refer to => Non-DTC Based Diagnostics. ABS Intermittent Condition Test

Test Step 2 - CHECK THE TERMINALS/CONNECTORS/WIRING HARNESS FOR DAMAGE


To avoid possible serious or fatal injury, on vehicles equipped with airbags, disable the supplemental restraint system before attempting any steering wheel, steering column, airbag, occupant classification system, seat belt tensioner, impact sensor, or instrument panel component diagnosis or service. Disconnect and isolate the battery negative (ground) cable, then wait two minutes for the system capacitor to discharge before performing further diagnosis or service. This is the only sure way to disable the supplemental restraint system. Failure to take the proper precautions could result in accidental airbag deployment.

• Proper Clockspring (SAS) installation is crucial for proper operation.

• Check the Clockspring installation.

• Check all related wiring for bruised, chafed, pierced, or partially broken wires.

• Check all related connectors for broken, bent, pushed out, or corroded terminals.

Were any problems found?

Yes

• Repair as necessary.

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

No

• Go to Test Step 3 => [ Test Step 3 - CHECK THE VOLTAGE ON THE (F943) FUSED IGNITION SWITCH
OUTPUT CIRCUIT ]

Test Step 3 - CHECK THE VOLTAGE ON THE (F943) FUSED IGNITION SWITCH OUTPUT CIRCUIT







• Turn the ignition off.

• Disconnect the Clockspring C3 (SAS) harness connector.

• Turn the ignition on.

• Measure the voltage of the (F943) Fused Ignition Switch Output circuit.

Is the voltage above 10 volts?

Yes

• Go to Test Step 4 => [ Test Step 4 - CHECK THE RESISTANCE OF THE (Z905) GROUND CIRCUIT ]

No

• Repair the (F943) Fused Ignition Switch Output circuit for an open.

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

Test Step 4 - CHECK THE RESISTANCE OF THE (Z905) GROUND CIRCUIT







• Turn the ignition off.

• Measure the resistance between the (Z905) Ground circuit and ground.

Is the resistance below 5.0 Ohms?

Yes

• Replace the Clockspring..

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

No

• Repair the (Z905) Ground circuit for an open.

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