DTC U0424-81: HVAC Control Module to Hybrid Powertrain Control Module Invalid Serial Data Received [04/2018 - 08/2020]: Procedure

1. Connect the Techstream to the DLC3.
2. Turn the power switch on (IG).
3. Enter the following menus: Body Electrical/Air Conditioner/Trouble Codes.
4. Check if DTCs related to the air conditioning system (A/C) are output.

   Body Electrical > Air Conditioner > Trouble Codes 

   Result

   Result	Proceed to
   DTCs related to A/C are not output.	A
   DTCs related to A/C are output.	B

5. Turn the power switch off.

Result: 

A 

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY. Refer to  REMOVAL [04/2018 - 08/2020] 

Result: 

B 

GO TO DTC CHART (AIR CONDITIONING SYSTEM). Refer to  DIAGNOSTIC TROUBLE CODE CHART [04/2018 - 08/2020]