Checking Control Unit Power Supply System

(2) CHECKING CONTROL UNIT POWER SUPPLY SYSTEM (lights do not go out)












[CHECK/1] Check fuse
1. Check that the fuse for the control unit power is not blown. When doing this, measure the voltage at the fuse also.







2. Judgement
- Fuse is blown -> replace fuse (voltage is normal)
- Fuse is normal -> go to [CHECK/2]
- Voltage is not as specified -> disconnection in harness between battery and fuse, abnormality in battery -> repair harness or inspect battery







[CHECK/2] Check that lights go out
1. Remove connector [I-70-2] from control unit.
2. Turn the ignition key switch ON.
3. Judgement
- Lamp stays ON -> abnormality in wiring harness of diagnostic light system -> repair or replace harness
- Lamp goes out -> go to [CHECK/3]







[CHECK/3] Check power circuit
1. Turn the ignition key switch ON.
2. Measure voltage between terminal (3) (+ end) and terminal (12) (- end) of instrument harness connector [I-70-2].







3. Judgement
- Voltage normal -> replace control unit
- Voltage abnormal -> go to [CHECK/4]







[CHECK/4] Check power circuit (+ end)
1. Turn the ignition key switch ON.
2. Measure voltage between terminal (3) (+ end) of instrument harness connector [I-70-2] and body ground (- end).







3. Judgement
- Voltage normal -> go to [CHECK/5]
- Voltage abnormal -> harness abnormal -> repair or replace







[CHECK/5] Check continuity of instrument harness
1. Check the continuity between the body and terminal (12) of instrument harness connector [I-70-2].
2. Judgement
- Continuity -> check again from [CHECK/3]
- No continuity -> harness abnormal -> repair of replace

NOTE: After completing each operation, carry out troubleshooting with the diagnostic light and confirm that there is no abnormality.