General Precautions of EFI System Maintenance
F-28
Step I: Use diagnostic instrument to read the malfunction information
Read Result I Read Result II
MIL Lamp On P-CODE Present MIL Lamp Off P-CODE Present
P0133
P0133
Maintenance tips:
The malfunction has been confirmed, and the
following problems may possibly exist
1) Sensor already aged and replacement required
Maintenance tips:
The malfunction has not been finally confirmed; wait
for ECU to fulfill the final test.
31. P0134 Upstream Oxygen Sensor Circuit Signal Malfunction
Description about Malfunction Cause:
After engine has been started, ECU will perform measurement on the circuit voltage of upstream oxygen
sensor, and the system will determine it to be the signal of upstream oxygen sensor in open circuit, when
signal voltage always maintain a certain value between 0.4~0.6V without change.
Schematic Circuit:
Malfunction Diagnostic Guide:
Required Equipment: (Diagnostic Instrument with EOBD Diagnostic Function, Digital Multimeter, and
Correct Circuit Diagram)
Step I: Use diagnostic instrument to read the malfunction information
Read Result I Read Result II
MIL Lamp On P-CODE Present MIL Lamp Off P-CODE Present
P0134
P0134
Maintenance tips:
The malfunction has been confirmed, and the
following problems may possibly exist
1) The circuit of oxygen sensor connected to the
Pin 18# of ECU in open circuit
2) The connector of oxygen sensor in bad contact
(pin oxidized)
Maintenance tips:
The malfunction is not ultimately confirmed and it
may possibly be a random malfunction. Inspect the
following items:
1) Measure the electric resistance of the Pin 18# for
connector of ECU to the Pin B# of oxygen
sensor.
Main relay
To Next Page
