General - Buell 2008 XB SERIES Electrical Diagnostics Manual

DTC P0151 (13), P0152 (11), P0154 (13)

GENERAL

Oxygen (O2) Sensor
See Figure 2-52. The oxygen sensor provides a signal to the
Electronic Control Module (ECM) which indicates whether the
engine is running rich or lean.
A low voltage signal (<0.41 V) indicates the engine is
running lean.
A high voltage signal (>0.56V) indicates the engine is
running rich.
When the air/fuel mixture is ideal, approximately 14.7 parts air
to 1 part fuel, the voltage will be approximately 0.48 V.
Table 2-35. Code Description
DTC CHECK
ENGINE
LAMP CODE
P0151 13
P0152 13
P0154 13
ed01474
1
1. Oxygen sensor
2. Connector [137]
Figure 2-52. Oxygen Sensor
2-66 2008 Buell XB Diagnostics: Engine Management
DESCRIPTION
Oxygen (O ) sensor circuit
2
low/engine lean
Oxygen (O ) sensor circuit
2
high/engine rich
Oxygen (O ) sensor
2
open/inactive
2
ed01475
Figure 2-53. Oxygen Sensor (shock absorber removed)
DIAGNOSTICS
PART NUMBER
B-48115 BREAKOUT BOX
HD-39978 DVOM
Diagnostic Tips
The DVOM (Part No. HD-39978) displays the signal from the
oxygen sensor in volts. This voltage will have an average value
tending towards lean, rich or ideal value depending on oper-
ating temperature of the engine, engine speed and throttle
position. An open/short to voltage or short to ground in the
(V/GY) wire will cause the engine to run rich (short to ground)
or lean (short to voltage) until fault is detected, vehicle will run
in open loop. The engine must be running below 5000 RPM
for the ECM to detect an oxygen failure.
Check for the following conditions:
Poor Connection: Inspect ECM harness connector, fuel
injector connectors and oxygen sensor connector [137]
wiring for backed out terminals, improper mating, broken
locks improperly formed or damaged terminals, poor ter-
minal-to-wire connection and damaged harness.
Dirty/Stuck Open Injectors: The motorcycle may run
lean (dirty/clogged injectors) or rich (stuck open injectors)
if there is an injector problem. This could also cause poor
fuel economy and performance.
Loose Oxygen Sensor: See
sensor is loose engine performance may be affected. This
could also show up as a slow changing oxygen sensor
voltage.
Loose/Leaking Exhaust: This can cause poor ground
connection for sensor or allow fresh air into the exhaust
system. If fresh air enters exhaust system, the oxygen
sensor will read a lean condition, causing the system to
go rich.
2.20
TOOL NAME
Figure 2-53. If the oxygen