| Last Modified: 07-31-2024 | 6.11:8.1.0 | Doc ID: RM100000001GEI1 |
| Model Year Start: 2020 | Model: Corolla | Prod Date Range: [01/2019 - 09/2022] |
| Title: 2ZR-FXE (ENGINE CONTROL): SFI SYSTEM: ECM Power Source Circuit; 2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022] | ||
|
ECM Power Source Circuit |
DESCRIPTION
When the power switch is turned on (IG), auxiliary battery voltage is applied to the IGSW terminal of the ECM. The output signal from the MREL terminal of the ECM causes current to flow to the coil of the No. 1 integration relay (EFI-MAIN relay), closing the contacts of the EFI-MAIN relay and supplying power to terminals +B and +B2 of the ECM.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Inspect the fuses for circuits related to this system before performing the following procedure.
PROCEDURE
|
1. |
CHECK HARNESS AND CONNECTOR (POWER SOURCE OF NO. 1 INTEGRATION RELAY) |
(a) Disconnect the No. 1 integration relay connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
2A-10 - Body ground |
Always |
11 to 14 V |
|
2B-3 - Body ground |
Always |
11 to 14 V |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR (AUXILIARY BATTERY - NO. 1 INTEGRATION RELAY) |
|
|
2. |
INSPECT NO. 1 INTEGRATION RELAY (EFI-MAIN RELAY, IG2 NO. 1 RELAY) |
(a) Inspect the No. 1 integration relay (EFI-MAIN relay, IG2 NO. 1 relay).
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![2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 09/2022]; POWER DISTRIBUTION: INTEGRATION RELAY: INSPECTION](/t3Portal/stylegraphics/info.gif)
| NG |
|
REPLACE NO. 1 INTEGRATION RELAY
|
|
|
3. |
CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - ECM) |
(a) Disconnect the No. 1 integration relay connector.
(b) Disconnect the ECM connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
2A-9 - A46-6 (IGSW) |
Always |
Below 1 Ω |
|
2B-6 - A46-46 (MREL) |
Always |
Below 1 Ω |
|
2B-4 - A46-2 (+B) |
Always |
Below 1 Ω |
|
2B-4 - A46-3 (+B2) |
Always |
Below 1 Ω |
|
2A-9 or A46-6 (IGSW) - Body ground and other terminals |
Always |
10 kΩ or higher |
|
2B-6 or A46-46 (MREL) - Body ground and other terminals |
Always |
10 kΩ or higher |
|
2B-4 or A46-2 (+B) - Body ground and other terminals |
Always |
10 kΩ or higher |
|
2B-4 or A46-3 (+B2) - Body ground and other terminals |
Always |
10 kΩ or higher |
HINT:
If a short is detected in any of the above circuits, there may be a malfunction in the circuit of a connected ECU.
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
4. |
CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - BODY GROUND) |
(a) Disconnect the No. 1 integration relay connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
2A-8 - Body ground |
Always |
Below 1 Ω |
|
2B-5 - Body ground |
Always |
Below 1 Ω |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
5. |
CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) |
(a) Disconnect the ECM connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
C77-59 (E1) - Body ground |
Always |
Below 1 Ω |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
6. |
INSPECT ECM (IGSW VOLTAGE) |
|
*a |
Front view of wire harness connector (to ECM) |
(a) Disconnect the ECM connector.
(b) Turn the power switch on (IG).
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
A46-6 (IGSW) - Body ground |
Power switch on (IG) |
11 to 14 V |
| OK |
|
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE
|
|
|
7. |
CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - NO. 1 INTEGRATION RELAY) |
(a) Disconnect the certification ECU (smart key ECU assembly) connector.
(b) Disconnect the No. 1 integration relay connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
I1-15 (IG1D) - 2A-7 |
Always |
Below 1 Ω |
|
I1-15 (IG1D) or 2A-7 - Body ground and other terminals |
Always |
10 kΩ or higher |
HINT:
If a short is detected in any of the above circuits, there may be a malfunction in the circuit of a connected ECU.
| OK |
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|