Honda BF135A - Baro Sensor Troubleshooting

BF135A•BF150A
5-80
• BARO Sensor Troubleshooting
MIL blinks 13 times.
1. Symptom reproduction test
-1. Reset the ECM.
-2. Turn the ignition switch OFF and connect the test har-
ness.
• Hold the sensor connector connected.
-3. Turn the ignition switch ON.
-4. Measure the voltage between the A-5 terminal (+) and
the A-2 terminal (–) of the test harness.
Is there 1.58 – 4.49V?
YES – Temporary failure (Disappeared)
NO – Perform "2. BARO sensor power supply line
open circuit check".
2. BARO sensor power supply line open circuit check
-1. Turn the ignition switch OFF and disconnect the BARO
sensor 3P connector.
-2. Turn the ignition switch ON. Measure the voltage
between the No. 3 (Brown/White) terminal of the
BARO sensor harness side 3P connector and the
body ground.
Is the voltage 4.75 – 5.25V?
YES – Perform "3. BARO sensor signal line open cir-
cuit check".
NO – Repair open in the wire between the BARO
sensor and the ECM.
3. BARO sensor signal line open circuit check
-1. Turn the ignition switch ON. Measure the voltage
between the No. 2 (White/Blue) terminal of the BARO
sensor harness side 3P connector and the body
ground.
Is the voltage 4.75 – 5.25V?
YES – Perform “4. BARO sensor signal line short cir-
cuit check”.
NO – Repair open in the wire between the BARO
sensor and the ECM.
4. BARO sensor signal line short circuit check
-1. Turn the ignition switch OFF and disconnect the ECM
connector B.
-2. Check for the continuity between the No. 2
(White/Blue) terminal of the BARO sensor harness
side 3P connector and the body ground.
Is there the continuity?
YES – Repair short in the wire between the ECM
and the BARO sensor.
NO – Perform "5. BARO sensor ground line open
circuit check".
A-2
A-5
BARO SENSOR HARNESS SIDE
3P CONNECTOR
VIEWED FROM THE TERMINAL SIDE
VCC2
(BROWN/WHITE)
BARO SENSOR HARNESS SIDE
3P CONNECTOR
VIEWED FROM THE TERMINAL SIDE
PA (WHITE/BLUE)
BARO SENSOR HARNESS SIDE
3P CONNECTOR
VIEWED FROM THE TERMINAL SIDE
PA (WHITE/BLUE)