Project 2

AUTOMOTIVE WIRING HARNESS FOR BACKDOOR

Aim: To route the wiring harness on the given backdoor assembly and prepare the flatten view drawing in CATIA V5.

Objective: The objective of this project is to route the wiring harness and prepare flatten view drawing for the Backdoor of the car. All types of packaging rules have to be considered while routing the harness and industry based practices shall be demonstrated in harness design. All necessary details like clearance, clipping/clamping selection, harness fixing requirements, harness continuity should be provided in order to design the wiring harness.

Introduction:

The trunk or boot of a car is the vehicle's main storage or cargo compartment it also have a hatch at the rear of the vehicle. It is also called a tailgate. These doors can be operated manually or electric powered. here we design the trunk or back door wire harness using the Catia.The Backdoor is an assembly of many parts such as inner panel, outer panel upper, outer panel lower and Reinforcement. Inner panel is attached to the outer panel using mastic sealant.

Types of doors based on working position

1. Top Mounted Door
2. Side mounted Door
3. Bottom Door

Rules to be followed:

1. Wiring harness should be routed in such way that it is easy to assemble and access.
2. Easy manufacturing, installation, removal and maintenance have to be considered while designing the wire harness.
3. wiring Harness should be kept away from sharp environment like edges, corners etc.
4. Avoid harness routing and clipping in the blind zones or hard to reach areas during harness assembly or service.
5. Provide additional slack if needed according to the surrounding and harness bending requirement. If harness is passing through the closures/doors or tail gates then envelope dimensions during opening and closing of doors shall be considered to provide the slack. Check the harness slack requirements with open and close conditions to avoid excess slack.
6. Routing through small structural holes and openings shall be avoided. To minimize chaffing and handling of the wiring harness during installation.
7. It should be make sure that there is no case of fouling while designing the wiring harness in the CAD environment. Additional mounting equipments like clips/clamps may be used to avoid fouling.
8. Use of rubber grommet is recommended if harness is passing through sheet metal panels. Example- firewall, passing to door, tail gate etc.
9. The branch length should be greater than 50mm.
10. The minimum distance between the clip and branch point should be at least 25mm.
11. The minimum distance between the two branch points should be at least 50mm.
12. Clips/clamps used for the wiring harness should be easily available in the market to avoid extra cost for custom mounting solutions.

STEP 1 - Creating context assembly

Open the Backdoor assembly in the CATIA software making an assembly product file.

STEP 2 - Defining connectors electrically

Taking required components for the wire harness routing. Here we are using the components for backdoor upper and lower lights, wiper motor, sensors, and defogging equipment. The connectors used are first electrically defined and then added to the CATIA model.

Connectors :-

1 Interconnector 

2 4Pole connector :-

3 Furr tree clip : -

Wire Harness Routing

Harness Assy 

Flattening 

Thnk you.