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.

CHECK ELECTRIC VEHICLE CONTROL UNIT (EVCU) DTCs
1. With the scan tool, read DTCs in the EVCU.
  Are there any EVCU Stop Lamp Switch related DTCs present?
  
  Yes
  - Perform the appropriate diagnostic procedure. Refer to ELECTRIC VEHICLE CONTROL UNIT (EVCU) MODULE - DIAGNOSTIC CODE INDEX - 500 - ELECTRIC .
  No
  - Go To 2
STOP LAMP SWITCH OPERATION
1. Start the engine.
2. Using the scan tool, monitor the brake pedal switch status while pressing the and releasing the brake pedal.
  Is the stop lamp Switch operating correctly?
  
  Yes
  - Replace the Anti-lock Brake System (ABS) Module in accordance with the service information. Refer to MODULE, ANTI-LOCK BRAKE SYSTEM, REMOVAL .
  - Perform the ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .
  No
  - Go To 3
BRAKE PEDAL PRESSURE
1. Using the scan tool, monitor the brake pedal pressure and the status of the brake pedal switch while slowly pressing the brake pedal.
  Was there Brake Pressure before the Brake Pedal Switch status changed?
  
  Yes
  - Go To 4
  No
  - Replace the Anti-lock Brake System (ABS) Module in accordance with the service information. Refer to MODULE, ANTI-LOCK BRAKE SYSTEM, REMOVAL .
  - Perform the ABS INTERMITTENT CONDITION diagnostic procedure. Refer to ABS INTERMITTENT CONDITION .
STOP LAMP SWITCH ADJUSTMENT
1. Perform the Stop Lamp Switch Adjustment procedure. Refer to SWITCH, STOP LAMP, INSTALLATION .
2. Using the scan tool, monitor the brake pedal pressure and the status of the brake pedal switch while slowly pressing the brake pedal.
  Was there Brake Pressure before the Brake Pedal Switch status changed?
  
  Yes
  - Replace the Anti-lock Brake System (ABS) Module in accordance with the service information. Refer to MODULE, ANTI-LOCK BRAKE SYSTEM, REMOVAL .
  - Perform the ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .
  No
  - Go To 5
ELECTRIC VEHICLE CONTROL UNIT (EVCU)
1. Replace the Stop Lamp Switch in accordance with the Service Information. Refer to SWITCH, STOP LAMP, REMOVAL .
2. Perform the EVCU VERIFICATION TEST. Refer to EVCU VERIFICATION TEST .
3. Start the engine.
4. Press and release the brake pedal.
5. With the scan tool, read the DTCs.
  Does the DTC remain active?
  
  Yes
  - Replace and program the Electric Vehicle Control Unit (EVCU) in accordance with the service information. Refer to UNIT, ELECTRIC VEHICLE CONTROL (EVCU), REMOVAL .
  - Perform the EVCU VERIFICATION TEST. Refer to EVCU VERIFICATION TEST .
  No
  - Test Complete.
  - Perform the ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .