This bulletin applies to 2017-2019 Hyundai Ioniq HEV/PHEV (hybrid/plug-in hybrid) vehicles equipped with 1.6L engine.
An ECM software logic update may be required for DTC P0128 (coolant temperature – coolant temp below thermostat regulating temperature). There may be no drivability issues.
Note: If voltage is below 12 volts, select Back on GDS and run the engine for at least 20 minutes to ensure adequate battery state of charge for reliable update results. Turn the ignition back on and try the update.
YEAR HEV/PHEV ECU P/N NEW ROM ID
2017.....HEV.................3910103HM0..................AE6NSGHF10F0
2018.....HEV.................39101-03HM2..................AE8NSGHF10F2
2018.....PHEV...............39101-03HS0...................AE8NSGHF1PF2
2019......HEV...............39101-03HM4.................AED9S6HE0SF4
2019......PHEV.............39101-03HS1...................AED9S6PE0SF4
Perform the update in GDS Auto Mode. If the ECU update starts but then fails in Auto Mode, perform the update in Manual Mode to recover. Manual mode passwords are as follows:
MENU PASSWORD
AE 1.6GDI HEV/PHEV DCT + IMMO 39101-03HM0..........1030
AE 1.6GDI HEV/PHEV DCT + IMMO 39101-03HM2...........1032
AE 1.6GDI HEV/PHEV DCT + IMMO 39102-03HS0.............1033
AE 1.6GDI HEV/PHEV DCT + IMMO 39101-03HM4............1034
AE 1.6GDI HEV/PHEV DCT + IMO 39101-03HS1.................1031
