Lifan 620. Service manual - part 15

27. DTC: P0508, Idle Speed Regulator Control Circuit Voltage Too Low    (see Table 1-40) 

 

Table 1-40 

S/N Operation Test 

Results 

Actions 

1 

Connect the diagnostic instrument and adapter, and turn the 

ignition switch to ON. 

 Next 

step 

Yes Next 

step 

2 

Disconnect the idle speed regulator. Check the resistance 

between pin A and pin D, as well as between pin B and pin C 

3 

1 

2 

3 

1 

ignition switch to ON. 

Yes Next 

step 

2 

Disconnect the idle speed regulator. Check the resistance 

between pin A and pin D, as well as between pin B and pin C 

of the regulator. Is the resistance about 53±5.3Ω under the 

temperature of 20 ?

℃

 

No 

Replace stepper motor 

Yes 

Repair or replace 

harness 

3 

Check for open circuit between the pin A, B, C, D of the 

regulator and the pin 65#, 66#, 67#, 64# of the ECU. 

No 

Diagnosis help 

 

61

30. DTC: P0560, System Voltage Signal Abnormal (see Table 1-43) 

 

Table 1-43 

S/N Operation Test 

Results 

Actions 

1 

Connect the diagnostic instrument and adapter, and turn the 

ignition switch to OFF. 

 Next 

step 

Yes Next 

step 

2 

Check the volatage with a multimeter. Is the voltage about 

12V? 

3 

4 

5 

1 

2 

3 

ECU and the pin 87# of the main relay repectively. Is the 

resistance too high? 

No Next 

step 

Yes Next 

step 

4 

Start the engine, check if the generator charging voltage is 

within 9-16V under different rotation speed. 

No Replace 

engine 

Yes Diagnosis 

help 

5 

Check the grounding point of the engine harness for normal 

operation. 

No 

Repair or replace 

harness 

62

32. DTC: P0601, Electronic Control Unit Check Code Unprogrammed    (see Table 1-45) 

Table 1-45 

S/N Operation Test 

Results 

Actions 

1 

Connect the diagnostic instrument and adapter, and turn the 

ignition switch to ON. 

 Next 

step 

Yes Next 

step 

2 

Clear the DTC, and check once again if the trouble is stable.

No Normal 

3 Replace 

ECU. 

End 

1 

2 

3 

1 

2 

3 

end of the relay. 

No 

Go to step 2 

Yes Replace 

relay 

4 

Measure the voltage between the pin 86# of the relay 

(control end) and the power supply negative pole with a 

multimeter. Is the voltage about 3.7V? 

No Next 

step 

Yes 

Repair or replace 

harness 

5 

Check for open circuit between the pin 86# of the relay 

(control end) and the 70# of the ECU with a multimeter. 

No Diagnosis 

help 

63

35. DTC: P0646, A/C Compressor Relay Control Circuit Voltage Too Low    (see Table 1-48) 

 

Table 1-48 

S/N Operation Test 

Results 

Actions 

1 

Connect the diagnostic instrument and adapter, and turn the 

ignition switch to OFF. 

 Next 

step 

Yes 

Go to step 4 

2 

Disconnect the A/C compressor relay, and turn the ignition 

switch to ON. Measure the voltage between pin 30#, 85# of 

the relay (power supply end) and the power supply negative 

3 

4 

5 

 

1 

2 

3 

No 

Go to step 2 

Yes Replace 

relay 

4 

Measure the voltage between the pin 86# of the relay 

(control end) and the power supply negative pole with a 

multimeter. Is the voltage about 3.7V? 

No Next 

step 

Yes 

Repair or replace 

harness 

5 

Check for short to power supply between the pin 86# of the 

relay (control end) and the 70# of the ECU with a multimeter.

No Diagnosis 

help 

64