TGB EST 1000, Руководство по обслуживанию

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4-2. FUEL INJECTION SYSTEM
4-2-23
O2 Sensor
Functional Description:
●
Use 8 ~ 16V DC power supply, has the 4-pin coupler, a power supply
pins for heater; for a heater control pin; signal for a grounding pin; O2
for a signal pin.
●
O2 Sensor output feedback signal to the ECU fuel ratio control in the
vicinity of 14.5 ~ 14.7, a closed-loop fuel control.
●
When the air-fuel ratio control in the near equivalent, CO / HC / Nox to
have the highest conversion efficiency.
Testing Procedures:
1. Voltage confirmed:
●
Removed O2 Sensor and the wire harness between the coupler.
●
Open the main switch, but not to start engine.
●
Use "volteg meter" DC stalls (DCV) to check inlet pressure sensor
voltage.
●
Confirmed working voltage:
Volteg meter negative access to the wire harness sensor coupler 2nd
pin (Gray/Red ).
Voltage meter positive access to the wire harness sensor coupler first
pin (Red ).
2. Resistance Confirmation
:
●
Removed O2 Sensor and the wire harness between the coupler.
●
Use of the "meter" Ohm stalls, Measurement O2 Sensor heater
resistance.
●
Measurement resistance value
Ohm meter negative access to the O2 sensor coupler 2nd pin (White).
Ohm meter negative access to the O2 sensor coupler first pin (White).
Detection judge:
●
Working voltage value: above 10V
●
Resistance value: 15
±
2
Ω
Treatment of abnormal phenomena:
●
O2 sensor damage, heater damaged or couplers to poor contact.
●
Check whether the abnormal wire harness lines.
●
O2 Sensor anomaly, the proposed replacement of the O2 Sensor
，
and
measurements again.
Confirmed working voltage
Resistance Confirmation