VT6L Maintenance  18. Controller Unit 
 
154  VT series Maintenance Manual    Rev.2 
 
Mount the optional block on the connector plate. 
Hexagon socket head bolts: 
6-M3×30 (with seal washer.    The bolts are supplied with the module.) 
Tightening torque: 2.0 ± 0.1 N·m 
Connect the relay cable as shown below. Be careful not to cross the cables. 
 
 
When mounting the optional block, make sure that a groove of the connector 
 
 
Optional Block 
Optional Block 
 
   
Be sure to embed the seal washers 
(supplied with the module) when 
tightening with hexagon socket head bolts. 
If the seal washers are not embedded, 
water protection performance may not be 
ensured. 
 
 
 
Make sure that there is no scratches and/or dust on the gasket mounting surface. 
If the gasket is damaged or dusty, water protection performance may not be 
ensured. 
 
Be sure to install the dust covers 
(supplied with the module) on the 
unused connectors. 
If the dust covers are not installed on 
connectors completely, water 
protection performance may not be 
ensured. 
   
Be sure to use the dedicated cable 
(supplied with the module) for 
communication. 
If other cables are used, water protection 
performance may not be ensured.