Komatsu PC88MR-10 Shop Manual page 531

No. Cause
7 Defective controller
Related circuit diagram
PC88MR-10
Procedure, measuring location, criteria and remarks
<Precautions for troubleshooting>
(1) Connector number indication method and handling of T-adapter
For troubleshooting, insert or connect T-adapters as follows unless
otherwise specified.
When "male" or "female" is not indicated with a connector number,
disconnect the connector, and insert T-adapter between the male
and female connectors.
When "male" or "female" is indicated with a connector number,
disconnect the connector, and connect T-adapter to the male or
female connector.
"Male and female" means male and female of connector pins, not
connector housings.
Male and female of connector pins and housing in DT series, etc, are
opposite to those described in this manual. Take care.
(2) Pin number description sequence and tester lead handling
For troubleshooting, connect the positive (+) and negative (-) leads as
shown below unless otherwise specified.
Connect the positive (+) lead to pin or wire indicated first.
Connect the negative (-) lead to a pin or wire indicated second.
This is the excerpted circuit diagram related to
troubleshooting
The circuit diagram contains the connector Nos.,
pin Nos., and connector colors related to the
failure.
The "/" in a connector number is either:
1) An abbreviation (of more than three letters)
Example: T/C (Torque Converter)
2) Different connector number at male and female
sides
Example: BREAK OUT/E24
The circuit diagram contains the destination or
source of the branch line in a wiring harness.
The arrow (io) indicates a rough installation
position on the given machine.
NO: Normally Open
NC: Normally Closed
Signal names such as GND and 24 V are included
in addition to connector numbers at junctions, etc.
in circuit diagrams.
Except for GND and 24 V, a signal name indicated
at a junction, etc. shows that the wire is connected
to another junction or controller at where the same
signal name is indicated.
40 Troubleshooting
Related information on troubleshooting
40-43