Possible causes for the open circuit are as follows. As the cause can exist in the connector/coupler or terminal, they need to be checked carefully.
When checking system circuits including an electronic control unit such as ecm, etc., It is important to perform careful check, starting with items which are easier to check.

|
Check each terminal visually for poor contact (possibly caused by dirt, corrosion, rust, entry of foreign object, etc.). At the same time, check to make sure that each terminal is fully inserted in the coupler and locked.
If contact tension is not enough, rectify the contact to increase tension or replace. The terminals must be clean and free of any foreign material which could impede proper terminal contact.

|
Locate abnormality, if any.

|
Battery
Continuity checkIgnition coil inspection
Refer to “electrical components location” in section 0a .
Ignition coil primary peak voltage
Remove the air cleaner box. Refer to “air cleaner box removal and
installation” in section 1d .
Disconnect all ignition coil. Refer to “ignition coil and spark plug
removal and installation” .
...
Air cleaner box removal and installation
Removal
Lift and support the fuel tank. Refer to “fuel tank
removal and installation” in section 1g (page 1g-
9).
Remove the air cleaner box cover. Refer to “air cleaner element removal
and installation” .
Remove the air cleaner mounting bolt.
Remove the air clea ...
Conrod crank pin bearing inspection and
selection
Refer to “engine bottom side disassembly” (page 1d-
49).
Refer to “engine bottom side assembly” .
Inspection
Inspect the bearing surfaces for any signs of fusion,
pitting, burn or flaws. If any, replace them with a
specified set of bearings.
Place the plastigauge axially along ...