Briggs & Stratton VANGUARD 810 EFI Repair Manual page 46

42
DTC P0131 Heated Oxygen (HO
Step
1. Disconnect and reconnect HO
ECM J2 (Black) connectors.
2. Turn Ignition ON, Engine OFF.
1
3. Clear codes.
4. Turn Ignition OFF, and then back ON.
5. Does DTC return?
1. Turn Ignition OFF.
2. Back probe terminal C (Grey/Black wire) of
HO sensor connector.
2
3. Connect terminal C back probe to red me-
ter test lead on DVOM.
4. Back probe terminal D (Brown wire) of HO
sensor connector.
2
5. Connect terminal D back probe to black
meter test lead on DVOM.
6. Set DVOM to read volts DC.
7. Start and run engine for at least 2 minutes.
8. With engine running, observe voltage on
DVOM.
9. Is reading 600 – 950 millivolts DC?
1. Turn Ignition OFF.
2. Remove probe from terminal C, and back
probe ECM connector terminal J2-17 (Grey/
Black wire).
3. Start and run engine.
3
4. Observe voltage on DVOM.
5. Is reading 600 – 950 millivolts DC?
A B C
C D
Figure 2-29 HO Sensor Connector.
2
Non-Scan Diagnostics
Action
sensor and
2
D
Yes
Go to step 2.
2
HO sensor
2
OK.
HO sensor
2
OK.
1
10
Figure 2-30 ECM J2 Connector (Black).
Section 2: Troubleshooting DTCs
) Sensor
2
Problem
corrected.
Go to step 3.
Verify that both HO
and ECM J2 (Black) connec-
tors are fully mated.
NOTE: If reading is below 300
millivolts DC, inspect exhaust
system for cracks or leaks
between muffl er and cylinder
head (gaskets). If everything
is OK, replace HO
9
18
J2-17
No
sensor
2
sensor.
2