The TCU will be reprogrammed and returned on the day of receipt.2000 BMW 328i (E46) Technical Service Bulletin # 720600 Date: 000601
Head Protection System - Airbag Replacement
GROUP 72
Safety Restraint Systems
Bulletin Number
72 06 00
Woodcliff Lake, NJ
June 2000
Service Engineering
SUBJECT:
HPS (Head Protection System) Airbag Replacement on E46 Vehicles
MODEL:
E46 sedan, 3 series produced up to 9/99
Situation:
Since September of 1999, the new type of front Head Protection System airbag was introduced into series production. Only the new type HPS
airbags will be available from the BMW Parts Distribution Centers for replacement purposes (e.g. after deployment caused by accident). In case the
new style Head Protection System airbag is retrofitted into an E46 sedan vehicle manufactured prior to 09/99, a certain modification to the airbag
mounting points in the vehicle is required, and for vehicles manufactured prior to 09/98 also the firing circuit harness must be modified. The table
provides part numbers for the new HPS airbags:
For a detailed installation instruction refer to the BMW Technical Information System (TIS) Repair Manual RA 72 12 020.
The procedure included in this Service Information Bulletin provides some additional information and installation hints which are not found in the
Repair Manual.
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Parts Information:
Warranty Information: For Information only.
Procedure
The new, modified HPS head airbag gas generator (from 09/99 production) has two locating lugs (1) and an oval bore (2) as mounting point.
In order to replace the HPS airbag, remove dashboard and headliner (follow the repair manual RA 72 12 020).
To modify vehicle installation points:
Drill two holes in the support tube for the instrument cluster to accommodate the locating lugs of the new HPS generator.
1. Mark out the dimensions for both bores on the instrument panel support tube:
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(A) = 25 mm; height measurement from the lower edge of support plate to the center of the lower hole.
(B) = 47 mm; height measurement from the lower edge of support plate to the center of the upper hole.
2. Mark out the dimensions for both holes on the instrument panel support tube:
(D) = 11.0 mm; side measurement from the inner edge of support plate to the center of lower hole.
(C) = 10.5 mm; side measurement from the inner edge of support plate to the center of the upper hole.
3. Drill two 8.5 mm holes (1, 2) at the marked points in the instrument panel support tube. Deburr bores, protect against rust, and remove
(vacuum) metal chips which were generated by drilling.
Important:
Make sure that no electric wires or other equipment components are in the area of the marked holes.
Remove, or protect them if necessary.
4. Install the HPS generator. The two locating lugs (1) of the generator must be inserted into two corresponding holes (2) in the support tube for
the instrument panel.
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5. During installation, the HPS airbag gas generator does not rest flush on the support plate for the instrument panel; there is an intentional gap
(A). Tightening the self-locking nut builds up a desired pretension, which provides additional security against release.
Only For Vehicles Manufactured Prior to 09/98
The HPS deflector plate should be replaced with the improved part:
1. HPS deflector plate up to 09/98 production
2. HPS deflector plate from 09/98 production (P/N 51 16 8 251 241 left side; P/N 51 16 8 251 242 right side).
The HPS deflector plate is located on top of the B-pillar. To remove the old style plate (prior to 09/98 production):
1. Unscrew bolt (1)
2. Slide HPS deflector plate upwards
3. Remove deflector plate towards the front.
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4. Drill one 6.5 mm hole in the location indicated (1) for additional mounting of the modified HPS deflector plate. Deburr bores, protect against
rust, and remove (vacuum) metal chips which were generated by drilling.
The new deflector plate is secured to the B-pillar by means of steel rivet-nut and M5 screw. BMW Service Engineering recommends using:
-- MAC Tools Nutsert Installation Kit TSN6S, and
-- Expander series steel rivet-nut ESMS 1OOBX (thread size 5 mm x 0.8, drill hole 6.5 mm).
5. Install one ESM5 100BX rivet nut into the hole in the B-pillar. Install the new style HPS deflector plate on the B-pillar as shown on the
illustration (e.g. right side).
Only for vehicles manufactured prior to 09/98:
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The connector for the HPS airbag gas generator has been changed, and the cable length must be extended by approx. 250 mm to accommodate the
altered location of the gas generator.
To modify the ignition circuit wiring harness:
6. Remove the short (about 12") intermediate harness (between generator and vehicle ignition harness connector) from the old type HPS
generator head. The round orange connector (vehicle harness side) is going to be reused in the modified harness.
7. At approximately 10" from the round orange connector (1), cut the pair of wires and strip off the insulation at the ends.
IMPORTANT:
The cuts must be slightly offset, so the crimping connectors will not be immediately adjacent to each other.
8. Use the "Airbag Repair Cable" PN 61 12 8 386 369. At approximately 10" from the yellow connector (2), cut the pair of wires and strip off
the insulation at the ends.
9. Connect the two parts of the modified harness by using crimping connectors (PN 61 13 8 353 746), and shrink tube insulations (PN 61 13 1
379 833) (# 3 on illustration S72 00 U07).
IMPORTANT:
Pin assignment in the modified harness are not relevant. For a detailed wire repair procedure for airbag ignition circuits, refer to SI Bulletin 61
