Howdy, y'all, new member here. I'm making a new engine harness from scratch and I'm a bit confused by how much current capacity I need my truck's wiring harness to have. Based on the fuse ratings, it needs to be able to handle 210A but that doesn't make sense to me because that would be about 7 10AWG wires and, from what I could tell, the older wiring harness only had about 3 10AWG wires. I haven't been able to find any information to explain this large difference in current capacity and I'm wondering if I'm missing something obvious. The fuses are listed below with the fuse ratings given by the truck's fuse box. If someone could set me straight, I would greatly appreciate it.
| Item | Type | Current (A) | Hot When |
| Stop/Hazard Lamps | Fuse | 15 | All Times |
| Power Door Locks | Fuse | 30 | All Times |
| Horn; Cigar Lighter | Fuse | 30 | All Times |
| Turn Lamps; Backup Lamps | Fuse | 15 | Accy |
| A/C-Heater | Fuse | 30 | Accy |
| Headlights | Fuse | 15 | Accy |
| Power Windows | Fuse | 30 | Accy |
| IGN | Breaker | 10 | All Times |
| FUEL | Breaker | 5 | All Times |
| START | Breaker | 30 | All Times |
