Lifan 620. Manual — part 19

Table 1-58 (Continued)

S/N Operation Test

Results

Actions

Yes Next

step

4

Check if the intake air manifold pressure is between

35kPa and 65kPa under idle speed.

No

Remove leakage for the air

intake system

Yes Next

step

5

Connect the fuel pressure gauge valve. Short-circuit the

pin 30 and the pin 87 of the fuel bump relay, and run the

fuel pump. Check if the fuel pressure is about 300kPa.

No 9

Yes 8

6

Connect the battery and the fuel injector with a special

7

8

9

10

11

12

13

15

Yes Next

step

16

Check the compressed pressure.

No

Remove the trouble

Yes Next

step

17

Check the resistance of the high voltage wire for each

cylinder. Is the resistance OK?

No Replace

Yes Replace

18

Check the ignition coil for damage or crack.

No Next

step

Yes Replace

ECU

19

Check the spark plug for normal operation.

No

Replace spark plug

77

9. Unstable idle speed or flameout under load (A/C etc)

Table 1-59

S/N Operation Test

Results

Actions

Yes

Remove the trouble

1

Turn the ignition switch to ON. Check if there is trouble

information records with a diagnostic instrument.

No Next

step

Yes Next

step

2

Turn on the A/C switch. Connect an adapter between

the ECU and the harness. Check the pin J1-09 and

J1-39 (A/C switch) of the ECU for signal input.

No

Check and repair A/C circuit

Yes Next

step

3

Check the A/C system pressure, electromagnetic clutch

4

5

6

1

2

3

4

Yes Next

step

5

Turn the ignition switch to ON. Connect an adapter

between the ECU and the harness. Check the voltage of

the pin J1-42 (intake air manifold absolute pressure

sensor output), J1-27 (intake air temperature sensor

output), J1-43 (coolant temperature sensor output),

J1-62, J1-06, J1-38 (oxygen sensor output), J1-01

(ignition switch), J1-54, J1-33, J1-53, J1-34 (output to

idle speed actuator). Is it OK?

No

Repair or replace harness

78

Table 1-60 (Continued)

S/N Operation Test

Results

Actions

Yes Next

step

6

Run the engine at an idle speed. Check if the ignition

advance angle is normal after the coolant reaches

normal operation.

No

Adjust ignition advance

angle

Yes Clean

up

7

Check if the sense hole of the intake air manifold

pressure and temperature sensor is blocked.

8

9

10

11

12

79

11. Idle speed too high

Table 1-61

S/N Operation Test

Results

Actions

Yes

Remove the trouble

1

Turn the ignition switch to ON. Check if there is

trouble information records with a diagnostic

instrument.

No Next

step

Yes

Adjust or replace

2

Check if the cable connected the the accelerator

3

4

5

6

7

8

9

10

Check the fuel injector seal ring for damage.

No

Replace seal ring

Yes Replace

ECU

11

Check the intake air manifold absolute pressure and

intake air temperature sensor for damage.

No Replace

sensor

80