Geely Emgrand X7. Manual part — 211

(a) Connect the fault diagnosis tester to the diagnostic interface.

(b) Turn ignition switch to ON position.

(c) Clear DTC code.

(d) Start and run the engine at idle speed to warm up the engine for at least 5 min.

(e) Read control system DTC code again to confirm that the system has no DTC code exported.

Step 13

Troubleshooting

5. Maintenance

guide

:

Refer to2.10.7.1 Replacement of Camshaft Position Sensor to replace the intake CMP sensor.

No

Refer to 2.2.7.3 Intermittent Fault
Inspection for intermittent fault.

Yes

843

2.12.7.37 DTC P0351 P0352 P0353 P0354

1. DTC

description:

DTC P0351

Cylinder 1 Ignition Circuit malfunction

DTC P0352

Cylinder 2 Ignition Circuit malfunction

DTC P0353

Cylinder 3 Ignition Circuit malfunction

DTC P0354

Cylinder 4 Ignition Circuit malfunction

Ignition coil #1 initiate the ignition for Cylinder #1; ignition coil #2 initiate the ignition for
Cylinder #2; ignition coil #3 initiate the ignition for Cylinder #3; ignition coil #4 initiate the
ignition for Cylinder #4. The ignition relay supplies power for the four ignition coils. ECM uses
the ECM harness connector EN01 terminal #4 to control Cylinder #1 ignition coil primary circuit
to be grounded; uses the terminal #1 to control Cylinder #2 ignition coil primary circuit to be
grounded; uses the terminal #62 to control Cylinder #3 ignition coil primary circuit to be grounded;
uses the terminal #81 to control Cylinder #4 ignition coil primary circuit to be grounded.

2. DTC Code Set Up and Removal Conditions:

DTC Code

DTC Detection
Strategy

Set(Control Strategy) Conditions Fault Locations

P0351

P0352

P0353

P0354

Hardware
Circuit
Inspection

Operating at idle, with the ignition
coil control end disconnected,
short to ground or short to power
supply, this DTC code will be set.
The fuel injection of the cylinder
with this DTC code will stop
leading to engine speed fluctuates.

1. Ignition

Coil

Circuit

2. Ignition

Coil

3. ECM

844

3. Circuit

figure

NL02-2098b

ECM

44

EN01

BAT

20A

E

F

22

MPR

86

87

30

85

发动机主继电器

4

EN01

1

EN01

A EN20

B EN20

C EN20

点火线圈

COILA

COILB

4. Diagnostic

Steps:

Refer to 2.10.6 “Diagnostic Information and Procedures” for ignition coil inspection.

5. Maintenance

guide

Refer to 2.10.7.3 “Replacement of Ignition Coil” to replace the ignition coil.

Engine
main relay

Ignition coil

845

2.12.7.38 DTC P0420

1. DTC

description:

ECM uses two oxygen sensors (front oxygen sensor and rear oxygen sensor) installed before and
after the three- way catalytic converters to monitor the conversion efficiency of the three-way
catalytic converter (TWC). ECM uses front oxygen sensor for Air-fuel ratio close-loop control and
monitors oxygen content in the exhaust gas not purified by TWC. The Post-catalytic oxygen
sensor sends voltage signal to ECM indicating the oxygen content in the exhaust gas purified by
the TWC. ECM compares signals from the two sensors to determine whether the TWC is currently
under normal working condition. If the calculated TWC conversion efficiency is too low, the fault
lamp will be lit and the DTC code will be set.

2. Conditions For Setting DTC and The Fault Location:

DTC Code

DTC Detection
Strategy

Conditions For Setting The DTC
(Control Strategy)

Fault Locations

P0420

Hardware
Circuit
Inspection

Coolant temperature is higher than
70°C (158 ?F), and the fuel system is
in close-loop mode. After driving
some distance and stop the vehicle,
run the engine at idle, the system
compares the front and rear oxygen
sensor signals to calculate three-way
catalyst converter oxygen storing
time. When the oxygen storing time is
less than the threshold, the system
reports a fault.

1. Front Oxygen

Sensor

2. Rear Oxygen

Sensor

3. Three-way

Catalytic
Converter.

4. Exhaust

Leak.

3. Circuit

sketch

Refer to 2.12.6 Electrical Schematic Diagram.

4. Diagnostic

Steps:

Note: Before carrying out this diagnosis step, observe the data list on fault diagnosis tester and
analyze the accuracy of the data, as these will help with quick diagnosis.

1

Inspect whether there are control system DTC codes other than DTC
P0420.

A. Connect fault diagnosis tester to the vehicle diagnostic interface.

B. Rotated ignition switch to ON position.

C. Press the power button of fault diagnosis tester.

D. Select the following menu items: Engine/Read DTC codes.

Read DTC code

Results

DTC Codes Shown

To Step

DTC P0420

Three-Way Catalytic Converter Conversion Efficiency Low

846