Method (1, 10) for manufacturing an electrical harness (30, 40, 50), said electrical harness (30, 40, 50) comprising at least one reference component (31, 41, 51, 51') and at least one secondary component (32, 42, 42', 42", 52, 52', 52", 53, 53') as well as at least one electrical wire (22, 22') extending between said at least one reference component (31, 41, 51, 51') and said at least one secondary component (32, 42, 42', 42", 52, 52', 52", 53, 53'), said electrical harness (30, 40, 50) including at least one protection sheath (34, 44, 44', 44", 54, 54', 54", 55, 55') for protecting said at least one electrical wire (22, 22') and at least two shrinkable sleeves (36-37, 46-49, 56-61), said at least two shrinkable sleeves (36-37, 46-49, 56-61) including at least one reference shrinkable sleeve (36, 46, 56, 59) and at least one secondary shrinkable sleeve (37, 47-49, 57, 58, 60, 61), said at least one reference shrinkable sleeve (36, 46, 56, 59) being arranged as covering at least partially said at least one reference component (31, 41, 51, 51') and said at least one protection sheath (34, 44, 44', 44", 54, 54', 54", 55, 55'), said at least one secondary shrinkable sleeve (37, 47-49, 57, 58, 60, 61) being arranged as covering at least partially said at least one secondary component (32, 42, 42', 42", 52, 52', 52", 53, 53') and said at least one protection sheath (34, 44, 44', 44", 54, 54', 54", 55, 55'), characterised in that said method (1, 10) includes at least the following steps: • assembly (2, 12) of said at least one electrical wire (22, 22'), of said at least one protection sheath (34, 44, 44', 44", 54, 54', 54", 55, 55'), of said at least two shrinkable sleeves (36-37, 46-49, 56-61), of said at least one reference component (31, 41, 51, 51') and said at least one secondary component (32, 42, 42', 42", 52, 52', 52", 53, 53'), said at least two shrinkable sleeves (36-37, 46-49, 56-61) being arranged in a non-shrunken state, • in a reference portion (131, 141, 151, 151') of said electrical harness (30, 40, 50), reference shrinkage (3, 13) of said at least one reference shrinkable sleeve (36, 46, 56, 59), said reference shrinkage step (3, 13) making it possible to immobilise said at least one protection sheath relatively with respect to said at least one reference component, said at least one reference component making it possible to assign at least one reference plane (P1, P2, P3, P4) to said electrical harness (30, 40, 50), • in a secondary portion (132, 142, 142', 142", 152, 152' 152", 153, 153') of said electrical harness (30, 40, 50) distinct from said reference portion (131, 141, 151, 151'), angular positioning (4, 14) of said at least one secondary component (32, 42, 42', 42", 52, 52', 52", 53, 53') with respect to said reference plane (P1, P2, P3, P4) according to a relative angular orientation (θ1), said relative angular orientation (θ1) being defined in a plane perpendicular to a longitudinal direction OX along which said at least one protection sheath (34, 44, 44', 44", 54, 54', 54", 55, 55') extends longitudinally facing said at least one secondary component (32, 42, 42', 42", 52, 52', 52", 53, 53'), • holding (5, 15) said at least one secondary component (32, 42, 42', 42", 52, 52', 52", 53, 53') in position in said relative angular orientation (θ1), and • secondary shrinkage (6, 16) of said at least at least one secondary shrinkable sleeve (32, 42, 42', 42", 52, 52', 52", 53, 53'), said reference shrinkage (3, 13) being sequentially operated before said secondary shrinkage (6, 16). • assembly (2, 12) of said at least one electrical wire (22, 22'), of said at least one protection sheath (34, 44, 44', 44", 54, 54', 54", 55, 55'), of said at least two shrinkable sleeves (36-37, 46-49, 56-61), of said at least one reference component (31, 41, 51, 51') and said at least one secondary component (32, 42, 42', 42", 52, 52', 52", 53, 53'), said at least two shrinkable sleeves (36-37, 46-49, 56-61) being arranged in a non-shrunken state, • in a reference portion (131, 141, 151, 151') of said electrical harness (30, 40, 50), reference shrinkage (3, 13) of said at least one reference shrinkable sleeve (36, 46, 56, 59), said reference shrinkage step (3, 13) making it possible to immobilise said at least one protection sheath relatively with respect to said at least one reference component, said at least one reference component making it possible to assign at least one reference plane (P1, P2, P3, P4) to said electrical harness (30, 40, 50), • in a secondary portion (132, 142, 142', 142", 152, 152' 152", 153, 153') of said electrical harness (30, 40, 50) distinct from said reference portion (131, 141, 151, 151'), angular positioning (4, 14) of said at least one secondary component (32, 42, 42', 42", 52, 52', 52", 53, 53') with respect to said reference plane (P1, P2, P3, P4) according to a relative angular orientation (θ1), said relative angular orientation (θ1) being defined in a plane perpendicular to a longitudinal direction OX along which said at least one protection sheath (34, 44, 44', 44", 54, 54', 54", 55, 55') extends longitudinally facing said at least one secondary component (32, 42, 42', 42", 52, 52', 52", 53, 53'), • holding (5, 15) said at least one secondary component (32, 42, 42', 42", 52, 52', 52", 53, 53') in position in said relative angular orientation (θ1), and • secondary shrinkage (6, 16) of said at least at least one secondary shrinkable sleeve (32, 42, 42', 42", 52, 52', 52", 53, 53'), said reference shrinkage (3, 13) being sequentially operated before said secondary shrinkage (6, 16).