Example Of A Troubleshooting Procedure - Subaru Legacy Reference Booklet

AN
INTRODUCTION T O
A B S 5.3 SYSTEM DIAGNOSIS
The Service Manual, Part T,
"Troubleshooting," Section 4-4 provides
the diagnostic procedure for trouble code
56, Detection of G-Sensor Stick. Be sure
you're looking at the diagnostic procedure
for the actual problem in this case; there
are three other diagnostic procedures for
trouble code 56!
Whenever a trouble code is set, the ABS
5.3 system stores the values of its inputs
and outputs. Before going further with the
diagnostic procedure, you can look at the
data display and see what the values were,
at the time the trouble code was set.
To do this, select "Each System Check," as
before. then select "ABS/TCS."
When the New Select Monitor asks
whether the vehicle has all-wheel drive and
automatic transmission, if the vehicle is
equipped with automatic transmission,
press the "Yes" button.
Now, select option # 5 , "Freeze Frame
Data."
New Select Monitor
-
"Freeze Frame
Data" Selected
From the Freeze Frame Menu, select "Data
Display." The New Select Monitor will
now give you values for 11 different para-
meters at the time the DTC was set. In this
example, Code 56, you would at least want
to know what the G-sensor voltage was,
when the code was set. You would also
want to take note of any other values that
are unusual.
Example of a Troubleshooting
Procedure
Let's look at the troubleshooting procedure
described in the Service Manual for Code
56
- Detection of G-Sensor Stick. As a first
step, the diagnostic procedure directs you
to "check all four wheels for free turning."
It asks, "Have the wheels been turning
freely, such as when the vehicle is lifted
up?" If so, it tells you the system is normal
- you should just erase the trouble code.
New Select Monitor
-
"Current Data Display
and Save" Selected
If not, the procedure tells you to use the
Select Monitor to check the voltage output
of the G sensor. Select Option 1, "Current
Data Display and Save" and use it to read
the G-sensor voltage. Depending on
whether the voltage reading is correct or
not, you would then troubleshoot the sen-
sor or the circuit, following the diagnostic
procedure in the Service Manual.
By the way, when the diagnostic procedure
tells you to check a connector, pay particu-
lar attention to it.
V i d e o R e f e r e n c e B o o k l e t
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