M20A-FKS (ENGINE CONTROL): ECM: REMOVAL; 2023 - 2025 MY Corolla Corolla Hatchback [03/2023

Last Modified: 07-31-2024	6.11:8.1.0	Doc ID: RM100000002B8RN
Model Year Start: 2023	Model: Corolla Hatchback	Prod Date Range: [03/2023 - ]
Title: M20A-FKS (ENGINE CONTROL): ECM: REMOVAL; 2023 - 2025 MY Corolla Corolla Hatchback [03/2023 - ]

REMOVAL

CAUTION / NOTICE / HINT

The necessary procedures (adjustment, calibration, initialization or registration) that must be performed after parts are removed and installed, or replaced during ECM removal/installation are shown below.

Necessary Procedures After Parts Removed/Installed/Replaced

Replaced Part or Performed Procedure	Necessary Procedure	Effect/Inoperative Function when Necessary Procedure not Performed	Link
1: w/ Smart Key System 2: w/o Smart Key System 3: w/ Steering Lock Function 4: If transaxle compensation code read from ECM *5: If transaxle compensation code not read from ECM
Replacement of ECM	Vehicle Identification Number (VIN) registration	MIL comes on
	for K121 ECU configuration	-
	Update ECU security key	Vehicle Control History (RoB) are stored
	ECU communication ID registration (Immobiliser system)	Engine start function
	for K120 Perform reset memory CVT oil pressure calibration Perform road test to allow TCM to learn	Large shift shock Deterioration of fuel efficiency	Initialization: Registration:
	for K121 Transfer transaxle compensation code4 Reset transaxle compensation code5 CVT oil pressure calibration Perform road test to allow ECM to learn	Large shift shock Deterioration of fuel efficiency	Initialization: Registration:
Replacement of ECM*1	Code registration (Smart Key System (for Gasoline Model, Start Function))	Wireless Door Lock Control System (for Gasoline Model with Smart Key System) Smart Key System (for Gasoline Model, Entry Function) Smart Key System (for Gasoline Model, Start Function) Steering lock function*3
Replacement of ECM*2	Code registration (Immobiliser system)	Engine start Telematics System

NOTICE:

If the ECM has been struck or dropped, replace it.

HINT:

When the cable is disconnected / reconnected to the battery terminal, systems temporarily stop operating. However, each system has a function that completes learning the first time the system is used.

Learning completes when vehicle is driven

Effect/Inoperative Function when Necessary Procedure not Performed	Necessary Procedure	Link
Front Camera System	Drive the vehicle straight ahead at 15 km/h (9 mph) or more for 1 second or more.

Learning completes when vehicle is operated normally

Effect/Inoperative Function when Necessary Procedure not Performed	Necessary Procedure	Link
*1: for Hatchback
Power Door Lock Control System Back door opener*1	Perform door unlock operation with door control switch or electrical key transmitter sub-assembly switch.

PROCEDURE

1. PRECAUTION

NOTICE:

After turning the engine switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal.

Click here

2. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL

Click here

3. REMOVE RADIATOR SUPPORT OPENING COVER

for Hatchback except GR
Click here
for Sedan with Illumination
Click here
for Sedan without Illumination
Click here

4. REMOVE INLET NO. 1 AIR CLEANER

Click here

5. REMOVE AIR CLEANER CAP WITH AIR CLEANER HOSE

Click here

6. REMOVE AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY

Click here

7. REMOVE AIR CLEANER CASE SUB-ASSEMBLY

(a) Remove the 2 bolts.

(b) Disengage the guide to remove the air cleaner case sub-assembly.

8. REMOVE ECM

(a) Disengage the claw and 2 guides to remove the No. 1 relay block cover from the No. 1 engine room relay block and No. 1 junction block assembly.

(b) Disconnect the 3 connectors from the No. 1 engine room relay block and No. 1 junction block assembly.

(c) Disengage the 2 claws to separate the engine wire from the No. 1 engine room relay block and No. 1 junction block assembly.

(d) Raise the 2 lock levers while pushing the locks on the levers, and disconnect the 2 ECM connectors.

NOTICE:

After disconnecting the ECM connectors, make sure that dirt, water or other foreign matter does not contact the connecting parts of the ECM connectors.

*A	for K120
*B	for K121
*1	Grommet

(e) Remove the bolt and disengage the wire harness clamp to separate the engine wire.

(f) Remove the grommet.

(g) Remove the bolt and nut.

(h) Disengage the guide to remove the ECM.

NOTICE:

If the ECM has been struck or dropped, replace it.

9. REMOVE NO. 2 ECM BRACKET

(a) Remove the 2 screws and No. 2 ECM bracket from the ECM.

10. REMOVE NO. 1 ECM BRACKET

(a) Remove the 2 screws and No. 1 ECM bracket from the ECM.