DTC U1064 (Front Seat Heater Control Unit)

DTC U1064  : Seat Heater Control Unit Lost Communication With Climate Control Unit

NOTE: 

• If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A .
• According to the detected DTC (s), check for the power circuit and the ground circuit of the control unit which cannot communicate with the front seat heater control unit.
• Refer to the DTC shown on the display, then inspect the connectors and terminals based on the instructions.

DTC (Front Seat Heater Control Unit)

1. Problem verification

   -1. Clear the DTCs with the HDS.

   -2. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

   -3. Wait for at least 6 seconds.

   -4. Check for DTCs with the HDS.

   DTC Description	DTC
   U1064 Seat heater control unit lost communication with climate control unit

   Is DTC U1064 indicated?

   YES 

   Go to step 2.

   NO 

   Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the transmitting control units and the front seat heater control.

2. Open wire check (B-CAN_H line, B-CAN_L line)

   -1. Turn the vehicle to the OFF (LOCK) mode.

   -2. Disconnect the receiving control unit connector.

   Front seat heater control unit 24P connector

   -3. According to the detected DTC on the following table, disconnect the transmitting control unit connector.

   DTC	Connector
   U1064	Climate control unit connector A (32P)

   -4. Check for continuity between the receiving control unit and the transmitting control unit on the B-CAN_H circuit and the B-CAN_L circuit.

   Test condition

   Vehicle OFF (LOCK) mode Front seat heater control unit 24P connector: disconnected Transmitting control unit connector for indicated DTC: disconnected

   DTC	Circuit name	Receiving control unit		Transmitting control unit
   		Connector	Terminal	Connector	Terminal
   U1064	B-CAN_H	Front seat heater control unit 24P connector	No. 10	Climate control unit connector A (32P)	No. 25
   	B-CAN_L		No. 9		No. 8

   Is there continuity?

   YES 

   The B-CAN_H wire and the B-CAN_L wire are OK.

   According to the detected DTC on the following table, substitute or replace the control unit based on the instructions (see table).

   DTC	Operation for transmitting control unit
   U1064	Substitute a known-good climate control unit , then recheck. If DTC U1064 goes away after substitution, replace the original climate control unit .

   NO 

   Repair an open in the B-CAN_H wire and/or the B-CAN_L wire between the front seat heater control unit and the transmitting control unit.