Diagnostic Test

WARNING: This page is about a different car, the 2015 Fiat 500. However, it is still accessible from the selected car via links, so may be relevant.

VERIFY THE DTC IS ACTIVE
NOTE:
This DTC must be active for the results of this test to be valid.
1. Perform any Service Bulletins that may apply
2. Ignition on.
3. With the scan tool, read and record DTCs.
4. Using the scan tool, read and record Environmental Data.
5. With the scan tool, erase ABS DTCs.
  WARNING:
  To avoid possible serious or fatal injury, check brake capability is available before road testing.
6. Test drive the vehicle in a straight line then turning the vehicle left and right in a curving manner between 15 and 35 km/h (9 and 22 mph).
7. With the scan tool, read DTCs.
  Is the DTC active at this time?
  
  Yes
  - Go To 2
  No
  - Test complete, the condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.
CHECK THE STEERING ANGLE
1. Start the engine.
2. Turn steering wheel so the wheels point in a straight ahead position.
3. With scan tool, read the steering angle.
  Is the Steering Angle reading within ±15° of 0°?
  
  Yes
  - Go To 3
  No
  - Go To 4
STEERING ANGLE ERRATIC SIGNAL
1. Start the engine.
2. With scan tool, graph the steering angle while slowly rotating the steering wheel from lock to lock.
  Is the Steering Angle displaying an erratic signal behavior?
  
  Yes
  - Go To 4
  No
  - Go To 5
CHECK FOR CORRECT INTERMEDIATE SHAFT ALIGNMENT INSTALLATION
2. Inspect the Intermediate shaft for proper alignment and correct installation in accordance with service information. Refer to SHAFT, INTERMEDIATE, INSTALLATION .
  Were any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .
  No
  
  NOTE:
  The Steering Angle Sensor (SAS) is internal to the steering column assembly and must be replaced as a complete unit.
  - Replace the Steering Angle Sensor (SAS) in accordance with service information. Refer to COLUMN, REMOVAL .
  - Perform the ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .
CHECK THE TERMINALS/CONNECTORS/WIRING HARNESS FOR DAMAGE
WARNING:
To avoid serious or fatal injury on vehicles equipped with airbags, disable the Supplemental Restraint System (SRS) before attempting any steering wheel, steering column, airbag, 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 SRS. Failure to take the proper precautions could result in accidental airbag deployment.

NOTE:
Proper Steering Angle Sensor (SAS) installation is crucial for proper operation.
1. Inspect the Steering Angle Sensor (SAS).
2. Check all related wiring for bruised, chafed, pierced, or partially broken wires.
3. Check all related connectors for broken, bent, pushed out, or corroded terminals.
  Were any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .
  No
  - Replace the Anti-lock Brake System (ABS) Module in accordance with service information. Refer to MODULE, ANTI-LOCK BRAKE SYSTEM, REMOVAL .
  - Perform the ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .