Lifan 620. Manual - part 40

2. ABS operation (pressure decrease) condition (Table 3-2 and Fig. 3-4). 

Table 3-2 

Solenoid valve 

Electricity 

Solenoid valve condition 

Normally opened valve 

On 

Closed 

Normally closed valve 

On 

Open 

 

Fig. 3-5 

The pressure of wheel slave cylinder is maintained by the closed normally opened valve and 

normally closed valve, when proper pressure is applied to the salve cylinder through increase or 

decrease of pressure.   

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4. ABS operation (pressure increase) condition (Table 3-4 and Fig. 3-6). 

Table 3-4 

Solenoid valve 

Electricity 

Solenoid valve condition 

Normally opened valve 

Off 

Open 

Normally closed valve 

Off 

Closed 

 

 

Fig. 3-7 

EBD is to guarantee the operation stability. Rear wheel will be stopped after front wheel. As front 

brake does more work than rear brake, the rear wheel will stop first if it receives equal pressure. In 

order to prevent it, the equipment, pressure reducing valve (P-Valve), to decrease the pressure of 

rear wheel is needed. A special P-Valve is not necessary for the vehicle with ABS, as ABS can 

control the rear wheel braking pressure with supplementary procedures and improve the operation 

stability. 

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Section III    Removal and Installation of ABS 

 

I. Spare Parts Supply Condition 

1. Difference between dry HECU and wet HECU (Fig. 3-8) 

 

 

 

RL). 

 

Fig. 3-9 

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2. Notes on HECU bracket assembly 

(1) As installation error may occur for the frictional resistance of buffer pad when tightening (3) 

bolts, lubricant not affecting physical property of buffer pad is preferred. 

(2) For easy operation, (3) bolts can be inserted into the buffer pad on bracket and then to HECU. 

(3) Make sure the tightening torque of (3) bolts is 20N·m with a special tool, torque wrench, as 

shown in Fig. 3-10.   

 

 

(5) Clean the surface with cleanser without mineral oil before removal. 

(6) Do not use compressed air or move the vehicle when system is opened. 

(7) Block the hydraulic pressure outlets with plugs as soon as possible after removal of ABS 

assembly. 

(8) Remove other parts hindering operation. 

(9) Use DOT#4 brake fluid. 

(10) Soak the seal component with brake fluid, not with engine oil or brake unguent. 

(11) Check for leakage of connectors of all hydraulic pipes. 

 

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