'61HN252' by American Honda Motor Co. - Page 470 of 540
http://services.honda.com/ServiceManual/SVC_MNL/61HN253/61HN2...
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3/9/2008 11:25 PM
[2005-2008] [TRX500 FA/FGA]
SELECTABLE 4WD SYSTEM
BEFORE STARTING
TROUBLESHOOTING
SELF-DIAGNOSTIC FUNCTION
The engine control module (ECM) that controls the
Selectable 4WD system has a self-diagnostic func-
tion to constantly monitor the system. The ECM
checks the condition of the Selectable 4WD system
by detecting the signals from each sensor and
device when the ignition switch is ON and during
driving. When the ECM detects a problem in the sys-
tem, the ECM overrides the 4WD selector switch,
puts the machine into 2WD, and 4WD cannot be
used.
· When the ECM detects a problem, it indicates the
4WD INDICATOR
problem by blinking the 4WD indicator.
Note how many times the indicator blinks, deter-
mine the detection item
(page 23-4)
and perform
the troubleshooting
(page 23-5).
· Only one current problem code will be indicated
even if two or more problems occur.
· Once the ECM detects a problem, it stores the
problem code in the erasable memory. It can be
indicated as freeze code by retrieval of problem
code (Retrieval and erasure procedure are the
same as the Hondamatic ones, refer to page
24-
9).
· The selectable 4WD function can be reset by
turning the ignition switch OFF and ON, but the
4WD selector stops functioning when the ECM
detects the problem again.
· After performing troubleshooting, erase the
problem code(s) and test-drive the vehicle to be
sure that the problem(s) has/have been repaired.
PROBLEM CODE BLINKING PATTERN:
1 sec.
1 sec.
3 sec.
1 sec.
"--"ON
Pattern
repeated
OFF
One Blink
Current problem code
(Example: Blinking 3 times =
Problem code 3)
PROBLEM CODE INDEX
Problem
Detection item
Refer to
code
2
Front vehicle speed sensor (VSS) circuit (no signal)
23-5
3
Rear vehicle speed sensor (VSS) circuit (no signal)
23-7
4
System voltage (out of specified value)
23-9
5
Front final clutch system circuit malfunction
23-9
23-4
