Two people (including children) should never attempt to use a single seat belt. This could increase the severity of injuries in case of an accident.
Kia Cee'd JD Service Manual: Cowl Cross Bar Assembly Components and components location
Component Location
1. Cowl cross bar assembly
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Kia Cee'd JD Service Manual: Idler Repair procedures
Removal and Installation
1.
Remove the drive belt.
(Refer to Timing System - "Dreve Belt")
2.
Remove the idler (A).
Tightening torque :
42.2 ~ 53.9 N.m (4.3 ~ 5.5 kgf.m, 31.1 ~ ...