User Manual

34
KohlerEngines.com 24 690 01 Rev. D
TroublshootingOxygen Sensor (O
2
)
Condition Possible Cause Conclusion
Low voltage output. Shorted sensor or sensor circuit.
Shorted lead wire.
Wiring shorted to ground.
Replace sensor or repair wiring.
Contamination of air reference. Remove source of external
contamination, protect air reference
area.
Air leak at sensor or gasket, sensor
upper shield damage.
Use recommended torque at
installation, replace gasket or sensor.
Revise application exhaust.
Shield sensor from damage.
High voltage output. Silica poisoning. Replace sensor.
Contaminated gasoline. Use high quality fuel.
(QJLQHSUREOHPPLV¿UH &RUUHFWFDXVHRIPLV¿UH
Excessive rich air/fuel ratio. Check for high fuel pressure.
Leaking injector.
Liquid fuel in vent line.
Wiring shorted to voltage. Repair wiring.
Open circuit, no activity from sensor. Broken element .
Sensor dropped.
Hard blow to engine or exhaust
system.
Defective sensor.
Thermal shock.
Replace sensor.
Slow time response. Open heater circuit.
Improper handling.
Carbon deposits.
Replace sensor.
Improper fueling. Correct fueling.
Incorrect or contaminated fuel. Use high quality fuel.
Excessive engine oil consumption
causing exhaust contamination or
other exhaust side contamination.
Correct engine condition.
Heater circuit open/shorted or out of
VSHFL¿FDWLRQ
Repair short in harness wires, replace
sensor.
Manifold Absolute Pressure Sensor (MAP)
A sealed, nonserviceable assembly. A faulty sensor
must be replaced. If a blink code indicates a problem
with manifold absolute pressure sensor, it can be tested
as follows:
1. Make sure all connections are making proper
contact and are free of dirt and debris. Remove
blower housing. Slide locking tab out and pull off
manifold absolute pressure connector. Turn key
switch to ON and check with a volt meter by
contacting red lead to pin 1 and black lead to pin 2.
There should be 5 volts present, indicating ECU and
wiring harness are functioning.
2. Check continuity in wire harness. Ohms between Pin
3 at sensor connector and Black pin 11 connector at
ECU should be near zero ohms. If no continuity is
measured or very high resistance, replace wire
harness.
3. Check to make sure intake manifold is not loose and
MAP sensor is not loose. Loose parts would allow a
vacuum leak, making MAP sensor report misleading
information to ECU.
a. Tighten all hardware and perform an ECU Reset
and a TPS Learn Procedure to see if MIL will
GLVSOD\DIDXOWZLWK0$3VHQVRUDJDLQ,I0,/¿QGV
a fault with MAP sensor, replace it.
DELPHI EFI