Geely EC718 2009 Workshop Manual page 196

2-114 Control System JL4G18-D
Pre-catalytic Oxygen Sensor
Harness Connector EN02
4
ECM Harness Connector EN01
64 63 62 61 60 59 58 57
50 49 48 47 46 45 44 43
36 35 34 33 32 31 30 29
22 21 20 19 18 17 16 15
Step 12 Check the pre-catalytic oxygen sensor ground circuit.
EC718/EC718RV EC715/EC715RV 10/2009
3 2 1
56 55 54 53 52 51
8 7
6
5
42 41 40 39 38 37
28 27 26 25 24 23
4 3
2 1
9
14 13 12 11 10
FE02-5045b
(a) Turn the ignition switch to "OFF" position.
(b) Disconnect oxygen sensor wiring harness connector EN02.
(c) Disconnect ECM harness connector EN01.
(d) Measure resistance between pre-catalytic oxygen sensor
wiring harness connector EN02 terminal No.4 and ECM
harness connector terminal No.45. Check whether the circuit
is open. If there is no open circuit, repair the faulty part.
(e) Measure resistance between pre-catalytic oxygen sensor
wiring harness connector EN02 terminal No.4 and a reliable
ground. Check whether the circuit is short to ground. If there
is no short circuit, repair the faulty part.
(f) Measure voltage between Pre-Catalytic oxygen sensor
wiring harness connector EN02 terminal No.4 and a reliable
ground. Check whether the circuit is short to power supply. If
there is no short circuit, repair the faulty part.
Test Items
Resistance Between EN02 (4) and EN01
(45)
Resistance Between EN02 (4) and a
Reliable Ground
Voltage Between EN02 (4) and a Reliable
Ground
Go to step 15
Normal
Engine
Standard Value
Less than 1 Ω
10 kΩ or higher
0 V