Lifan 620. Service manual - part 70

11. Check for driver safety belt pre-tensioner 
(1) Measure the resistance between the RLP+ and RLP- at one side of the air bag ECU. Normal 
resistance shall be above 1MΩ. 
(2) Measure the resistance between the RLP+ at one side of the air bag ECU and RLP+ at one 
side of the driver safety belt pre-tensioner. Normal resistance shall be within 1Ω. 
(3) Measure the resistance between the RLP- at one side of the air bag ECU and RLP- at one side 
of the driver safety belt pre-tensioner. Normal resistance shall be within 1Ω. 

1. Check for constant illumination when ignition switch at LOCK 
(1) Turn the ignition switch to position LOCK. 
(2) Remove the negative ground wire from the battery and wait for at least 3min. 
(3) Unplug the air bag ECU interface. 
(4) Connect the ground wire to the battery negative pole and wait for at least 3min. 
(5) Check whether the SRS warning lamp goes out or not. If it goes out, the air bag ECU shall be 

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renewed; if not, check the SRS warning lamp circuit. 

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Section III    Diagnosis of Vehicles after Collision 

Check and maintain the vehicles after collision even without the deployment of air bag. Refer to 
Section IV for related methods of removal and installation. 

 
I. Diagnosis, with the deployment of air bag 

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5. Front passenger safety belt pre-tensioner. Check the front passenger safety belt pre-tensioner 
for depression, crack and distortion, the harness and interface for damage and the terminal for 
distortion. Check the pre-tensioner for normal installation. Renew if necessary. 
6. Clock spring. Check the interface and harness of the clock spring for damage and the circuit 
performance of the clock spring as per 2.3.14. Renew as required. 
7. Harness. Check the air bag harness for firmness, the harness and interface for damage and the 
terminal for distortion. Renew if necessary. 

Note:

 Replace the entire air bag components if they are soaked by water.   

8. Press the SST switch and deploy the air bag. With the LED lamp of the SST switch on, the air 
bag deploys simultaneously. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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