DTC P1616: Communication Error from ECM to Distance Control ECU [08/2015 - 08/2019]: Procedure

CONFIRM DESIGNATION INFORMATION
1. Confirm the designation information.
  1. Turn the engine switch on (IG).
  2. Turn the cruise control switch on.
  3. With the brake pedal depressed, push the cruise control switch to +RES 3 times within 3 seconds. Check that the skid control buzzer sounds at this time.
    OK
    
    The skid control buzzer sounds (initialization is performed).
    NOTE:
    Do not turn the light control switch on at this time as doing so causes the beam axis to deviate. If the light control switch is turned on by mistake, readjust the beam axis (Refer to ADJUSTMENT [08/2015 - 08/2019] ).
    
    If initialization cannot be performed, first inspect the stop light switch circuit, cruise control switch circuit and skid control buzzer circuit.
  4. Turn the engine switch off.
Result:

NEXT

See step 2
CHECK FOR DTC
1. Clear the DTCs (Refer to DTC CHECK / CLEAR [08/2015 - 08/2019] ).
2. Perform the following to make sure the DTC detection conditions are met.
  HINT:
  
  If the detection conditions are not met, the system cannot detect the malfunction.
  1. Drive the vehicle at a speed of 50 km/h (30 mph) or more.
  2. Turn the cruise control switch on.
3. Check for DTCs (Refer to DTC CHECK / CLEAR [08/2015 - 08/2019] ).
  OK
  
  DTC P1616 is not output.
Result:

OK

END

Result:

NG

See step 3
REPLACE ECM
1. Replace the ECM (Refer to REMOVAL [08/2015 - ] ).
Result:

NEXT

See step 4
CHECK FOR DTC
1. Clear the DTCs (Refer to DTC CHECK / CLEAR [08/2015 - 08/2019] ).
2. Perform the following to make sure the DTC detection conditions are met.
  HINT:
  
  If the detection conditions are not met, the system cannot detect the malfunction.
  1. Drive the vehicle at a speed of 50 km/h (30 mph) or more.
  2. Turn the cruise control switch on.
3. Check for DTCs (Refer to DTC CHECK / CLEAR [08/2015 - 08/2019] ).
  OK
  
  DTC P1616 is not output.
Result:

OK

END (ECM IS DEFECTIVE)

Result:

NG

REPLACE DRIVING SUPPORT ECU

(Refer to REMOVAL [08/2015 - 08/2019] )