Subaru XT 1988 Service Manual page 306

FUEL INJECTION SYSTEM 2-7
(4) Measure resistance between the body and ground
terminals (B) and (BR).
Specified resistance:
lOn, max.
If resistance is greater than lOn, check the harness and
internal circuits of the control unit for discontinuity, and
the ground terminal on the intake manifold for poor
contact.
Fig. 25
(5) Turn the ignition switch ON (engine off).
(S)
Connect the air flow meter connector.
(7)
Measure voltage across power terminal (R) and the
body.
Specified voltage:
10V, min.
If voltage is outside specifications, check the condition of
the parts (battery, fuse, control unit harness, connector,
etc.) in the power line.
Fig. 26
(8) Attach the positive lead of a tester to signal terminal
(W)
and the negative lead to the ground terminal
(BR).
Measure the voltage across the two terminals.
Specified voltage:
1- 2V
If voltage is outside specifications, replace the air flow
meter.
L2-1099
Fig.
27
(9)
Remove the air flow meter from the air cleaner.
(The air intake boot need not be removed.)
(10) Blow air from the air cleaner side to check if voltage
across terminals
(W)
and (BR) is greater than that meas-
ured in step (8) above. If not, replace the air flow meter.
L2-1100
Fig. 28
19
(11) Install the air flow meter on the air cleaner.
(12) Start the engine.
(13) Warm up the engine until the coolant temperature
reaches approximately 80°C (17SoF).
(14) Drive at speed greater than 24 km/h (15 MPH) for
at least one minute.