Inspection - Honda BF135A Manual

BF135A•BF150A
6. Signal line open circuit check
-1. Turn the ignition switch OFF and disconnect the IAB
control valve 2P connector.
-2. Turn the ignition switch ON. Measure the voltage
between the No.1 (Yellow/Black) terminal of the IAB
control valve harness side 2P connector and the
engine ground.
IAB CONTROL VALVE HARNESS
SIDE 2P CONNECTOR
VIEWED FROM THE TERMINAL SIDE
Is there the battery voltage?
YES – Perform "7. IAB control valve check".
NO – Repair open in the wire between the ECM
and the IAB control valve
7. IAB control valve check
-1. Turn the ignition switch OFF. Disconnect the IAB con-
trol valve 2P connector.
-2. Measure the resistance between the IAB control valve
side 2P connector terminals.
Is the resistance 37 – 44 ?
YES – Substitute a known-good ECM and recheck.
NO – Replace the IAB control valve.
YELLOW/BLACK
• Shutter Valve Diaphragm Inspection
NOTICE
• Do not try to adjust the full close stop screw.
• Note that the shutter valve diaphragm must not be dis-
assembled. If replacement is necessary, replace as an
assembly of the intake manifold assembly.
1) Check the following.
• Check the shutter valve shaft for play and the stuck
shaft.
• Check the shutter valve for smooth movement from
the full open to the full close positions.
• Check there is no clearance between the full close
screw and the full close stopper when the shutter
valve is in the full close position.
• Move the shutter valve to the full open position and
check that the shutter valve contacts the full open
stopper.
SHUTTER VALVE DIAPHRAGM
FULL OPEN STOPPER
2) If there is any abnormality, clean the shutter valve
diaphragm with a contact cleaner and recheck.
If it is still abnormal, replace the intake manifold
assembly.
STOP SCREW
5-110