Honda BF135A Manual page 203

BF135A•BF150A
DTC 48-6: A/F sensor V current is abnormal
1. Symptom reproduction test
-1. Connect the HDS pocket tester and clear the DTC
once. If the DTC can not be cleared, go on the trou-
bleshooting.
-2. Start the engine and warm it up 5 minutes or more by
running the engine at 3,000 min
-3. Check the DTC again using the HDS pocket tester.
Does the DTC 48-6 appear?
YES – Perform "2. A/F sensor line short circuit
check".
NO – Temporary failure (Disappeared)
2. A/F sensor line (V line) short circuit check
-1. Turn the ignition switch OFF. Disconnect the A/F sen-
sor connector and the ECM connector A.
-2. Check for the continuity between the No. 1
(White/Black) terminal of the A/F sensor harness side
4P connector and the engine ground.
A/F SENSOR HARNESS
SIDE 4P CONNECTOR
AFV1
(WHITE/BLACK)
VIEWED FROM THE
TERMINAL SIDE
Is there the continuity?
YES – Repair short in the wire between the A/F sen-
sor and the ECM.
NO – Replace the A/F sensor and recheck. If there
is any abnormality, substitute a known-good
ECM and recheck.
-1 (rpm) under no load.
DTC 48-7: A/F sensor C current is abnormal
1. Symptom reproduction test
-1. Connect the HDS pocket tester and clear the DTC
once. If the DTC can not be cleared, go on the trou-
bleshooting.
-2. Start the engine and warm it up for 5 minutes or more
by running the engine at 3,000 min
load.
-3. Check the DTC again using the HDS pocket tester.
Does the DTC 48-7 appear?
YES – Perform "2. A/F sensor line short circuit
check".
NO – Temporary failure (Disappeared)
2. A/F sensor line (C line) short circuit check
-1. Turn the ignition switch OFF. Disconnect the A/F sen-
sor connector and the ECM connector A.
-2. Check for the continuity between the No. 2
(Black/Yellow) terminal of the A/F sensor harness
side 4P connector and the engine ground.
A/F SENSOR HARNESS SIDE
4P CONNECTOR
VIEWED FROM THE
TERMINAL SIDE
Is there the continuity?
YES – Repair short in the wire between the A/F sen-
sor and the ECM.
NO – Replace the A/F sensor and recheck. If it is
abnormal, substitute a known-good ECM and
recheck.
-1 (rpm) under no
AFC1
(BLACK/YELLOW)
5-50