ECU Power Source Circuit [11/2015 - ]: Procedure
- CHECK HYBRID VEHICLE CONTROL ECU (+B1, +B2 VOLTAGE)
- Turn the power switch on (IG).
- Measure the voltage according to the value(s) in the table below.
*a Component with harness connected
(Hybrid Vehicle Control ECU)- - Standard Voltage
(A50, F3)
(A50)
(F3)
Tester Connection Condition Specified Condition A50-11 (+B1) - Body ground Power switch on (IG) 11 to 14 V F3-1 (+B2) - Body ground Power switch on (IG) 11 to 14 V - Turn the power switch off.
Result
Proceed to OK NG
Result:
NG
See step 3
Result:
OK
See step 2
- CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - BODY GROUND)
- Disconnect the F2 and F3 hybrid vehicle control ECU connectors.
- Measure the resistance according to the value(s) in the table below.
*a Front view of wire harness connector
(to Hybrid Vehicle Control ECU)- - Standard Resistance
(F3, F2)
(F3)
(F2)
Tester Connection Condition Specified Condition F3-3 (E1) - Body ground Always Below 1 Ω F2-34 (E12) - Body ground Always Below 1 Ω F2-12 (E01) - Body ground Always Below 1 Ω F2-11 (E02) - Body ground Always Below 1 Ω F2-10 (E03) - Body ground Always Below 1 Ω - Reconnect the F2 and F3 hybrid vehicle control ECU connectors.
Result
Proceed to OK NG
Result:
OK
GO TO PROBLEM SYMPTOMS TABLE. Refer to PROBLEM SYMPTOMS TABLE [11/2015 - 11/2017] , or refer to PROBLEM SYMPTOMS TABLE [11/2017 - 12/2018] , or refer to PROBLEM SYMPTOMS TABLE [12/2018 - ]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
- CHECK HYBRID VEHICLE CONTROL ECU (MREL VOLTAGE)
- Turn the power switch on (IG).
- Measure the voltage according to the value(s) in the table below.
*a Component with harness connected
(Hybrid Vehicle Control ECU)- - Standard Voltage
(A50)
(A50)
Tester Connection Condition Specified Condition A50-5 (MREL) - Body ground Power switch on (IG) 11 to 14 V - Turn the power switch off.
Result
Proceed to OK NG
Result:
NG
REPLACE HYBRID VEHICLE CONTROL ECU. Refer to REMOVAL [11/2015 - 12/2018] , or refer to REMOVAL [12/2018 - 08/2019] , or refer to REMOVAL [08/2019 - 07/2020] , or refer to REMOVAL [07/2020 - ]
Result:
OK
See step 4
- CHECK FUSE (PM-IGCT)
- Remove the PM-IGCT fuse from the No. 1 engine room relay block and No. 1 junction block assembly.
*1 No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly *2 PM-IGCT Fuse - Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition PM-IGCT fuse terminals Always Below 1 Ω - Install the PM-IGCT fuse.
Result
Proceed to OK NG
Result:
NG
See step 11
Result:
OK
See step 5
- Remove the PM-IGCT fuse from the No. 1 engine room relay block and No. 1 junction block assembly.
- CHECK FUSE (IGCT-IG)
- Remove the IGCT-IG fuse from the No. 1 engine room relay block and No. 1 junction block assembly.
*1 No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly *2 IGCT-IG Fuse - Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition IGCT-IG fuse terminals Always Below 1 Ω - Install the IGCT-IG fuse.
Result
Proceed to OK NG
Result:
NG
See step 12
Result:
OK
See step 6
- Remove the IGCT-IG fuse from the No. 1 engine room relay block and No. 1 junction block assembly.
- INSPECT RELAY (IGCT)
- Remove the IGCT relay from the No. 1 engine room relay block and No. 1 junction block assembly.
*1 No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly *2 IGCT Relay - Measure the resistance according to the value(s) in the table below.
*1 IGCT Relay Standard Resistance
Tester Connection Condition Specified Condition 3 - 5 Auxiliary battery voltage not applied between terminals 1 and 2 10 kΩ or higher Auxiliary battery voltage applied between terminals 1 and 2 Below 1 Ω - Install the IGCT relay.
Result
Proceed to OK NG
Result:
NG
REPLACE RELAY (IGCT)
Result:
OK
See step 7
- Remove the IGCT relay from the No. 1 engine room relay block and No. 1 junction block assembly.
- CHECK HARNESS AND CONNECTOR (NO. 1 ENGINE ROOM RELAY BLOCK AND NO. 1 JUNCTION BLOCK ASSEMBLY - HYBRID VEHICLE CONTROL ECU)
- Disconnect the A50 and F3 hybrid vehicle control ECU connectors.
- Remove the PM-IGCT fuse from the No. 1 engine room relay block and No. 1 junction block assembly.
*1 No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly *2 PM-IGCT Fuse - Measure the resistance according to the value(s) in the table below.
*1 No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly *2 PM-IGCT Fuse *a Front view of wire harness connector
(to Hybrid Vehicle Control ECU)- - Standard Resistance
(A50, F3)
(A50)
(F3)
Tester Connection Condition Specified Condition A50-11 (+B1) - 2 (PM-IGCT fuse) Always Below 1 Ω F3-1 (+B2) - 2 (PM-IGCT fuse) Always Below 1 Ω - Reconnect the A50 and F3 hybrid vehicle control ECU connectors.
- Install the PM-IGCT fuse.
Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 8
- CHECK HARNESS AND CONNECTOR (NO. 1 ENGINE ROOM RELAY BLOCK AND NO. 1 JUNCTION BLOCK ASSEMBLY)
- Remove the IGCT-IG fuse, PM-IGCT fuse and IGCT relay from the No. 1 engine room relay block and No. 1 junction block assembly.
*1 No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly *2 PM-IGCT Fuse *3 IGCT-IG Fuse *4 IGCT Relay - Measure the resistance according to the value(s) in the table below.
*1 No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly *2 PM-IGCT Fuse *3 IGCT-IG Fuse *4 IGCT Relay Standard Resistance
Tester Connection Condition Specified Condition 3 (IGCT relay) - 2 (IGCT-IG fuse) Always Below 1 Ω 5 (IGCT relay) - 1 (PM-IGCT fuse) Always Below 1 Ω - Install the IGCT-IG fuse, PM-IGCT fuse and IGCT relay.
Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 9
- Remove the IGCT-IG fuse, PM-IGCT fuse and IGCT relay from the No. 1 engine room relay block and No. 1 junction block assembly.
- CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - NO. 1 ENGINE ROOM RELAY BLOCK AND NO. 1 JUNCTION BLOCK ASSEMBLY)
- Disconnect the A50 hybrid vehicle control ECU connector.
- Remove the IGCT relay from the No. 1 engine room relay block and No. 1 junction block assembly.
*1 No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly *2 IGCT Relay - Measure the resistance according to the value(s) in the table below.
*1 No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly *2 IGCT Relay *a Front view of wire harness connector
(to Hybrid Vehicle Control ECU)- - Standard Resistance
(A50)
(A50)
Tester Connection Condition Specified Condition A50-5 (MREL) - 1 (IGCT relay) Always Below 1 Ω A50-5 (MREL) or 1 (IGCT relay) - Body ground and other terminals Always 10 kΩ or higher - Install the IGCT relay.
- Reconnect the A50 hybrid vehicle control ECU connector.
Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 10
- CHECK HARNESS AND CONNECTOR (NO. 1 ENGINE ROOM RELAY BLOCK AND NO. 1 JUNCTION BLOCK ASSEMBLY - BODY GROUND)
- Remove the IGCT relay from the No. 1 engine room relay block and No. 1 junction block assembly.
*1 No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly *2 IGCT Relay - Measure the resistance according to the value(s) in the table below.
*1 No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly *2 IGCT Relay Standard Resistance
Tester Connection Condition Specified Condition 2 (IGCT relay) - Body ground Always Below 1 Ω - Install the IGCT relay.
Result
Proceed to OK NG
Result:
OK
CHECK FOR INTERMITTENT PROBLEMS. Refer to CHECK FOR INTERMITTENT PROBLEMS [11/2015 - ]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
- Remove the IGCT relay from the No. 1 engine room relay block and No. 1 junction block assembly.
- CHECK HARNESS AND CONNECTOR (NO. 1 ENGINE ROOM RELAY BLOCK AND NO. 1 JUNCTION BLOCK ASSEMBLY - HYBRID VEHICLE CONTROL ECU)
- Remove the PM-IGCT fuse from the No. 1 engine room relay block and No. 1 junction block assembly.
*1 No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly *2 PM-IGCT Fuse - Disconnect the A50 and F3 hybrid vehicle control ECU connectors.
- Measure the resistance according to the value(s) in the table below.
*1 No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly *2 PM-IGCT Fuse *a Front view of wire harness connector
(to Hybrid Vehicle Control ECU)- - Standard Resistance
(A50, F3)
(A50)
(F3)
Tester Connection Condition Specified Condition A50-11 (+B1) or 2 (PM-IGCT fuse) - Body ground and other terminals Always 10 kΩ or higher F3-1 (+B2) or 2 (PM-IGCT fuse) - Body ground and other terminals Always 10 kΩ or higher - Reconnect the A50 and F3 hybrid vehicle control ECU connectors.
- Install the PM-IGCT fuse.
Result
Proceed to OK NG
Result:
OK
REPLACE FUSE (PM-IGCT)
Result:
NG
See step 13
- Remove the PM-IGCT fuse from the No. 1 engine room relay block and No. 1 junction block assembly.
- CHECK HARNESS AND CONNECTOR (NO. 1 ENGINE ROOM RELAY BLOCK AND NO. 1 JUNCTION BLOCK ASSEMBLY)
- Disconnect the IGCT-IG fuse, PM-IGCT fuse and IGCT relay from the No. 1 engine room relay block and No. 1 junction block assembly.
*1 No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly *2 PM-IGCT Fuse *3 IGCT-IG Fuse *4 IGCT Relay - Measure the resistance according to the value(s) in the table below.
*1 No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly *2 PM-IGCT Fuse *3 IGCT-IG Fuse *4 IGCT Relay STANDARD RESISTANCE:Tester Connection Condition Specified Condition 3 (IGCT relay) or 2 (IGCT-IG fuse) - Body ground and other terminals Always 10 kΩ or higher 5 (IGCT relay) or 1 (PM-IGCT fuse) - Body ground and other terminals Always 10 kΩ or higher - Install the IGCT-IG fuse, PM-IGCT fuse and IGCT relay.
Result
Proceed to OK NG
Result:
OK
REPLACE RELAY (IGCT-IG)
Result:
NG
See step 14
- Disconnect the IGCT-IG fuse, PM-IGCT fuse and IGCT relay from the No. 1 engine room relay block and No. 1 junction block assembly.
- REPAIR OR REPLACE HARNESS OR CONNECTOR
Result
Proceed to NEXT Result:
NEXT
REPLACE FUSE (PM-IGCT)
- REPAIR OR REPLACE HARNESS OR CONNECTOR
Result
Proceed to NEXT Result:
NEXT
REPLACE FUSE (IGCT-IG)