Noise When Electric Seat Fore/Aft Adjustment Is Activated
Noise When Electric Seat Fore/Aft Adjustment Is Activated
Model year: as of 2002 up to 2005
Vehicle Type: 911 Carrera (996)/911 Carrera 4 (996)/911 GT3 (996)
Equipment: Electrically adjustable front seats (I-no. 537/538).
Concerns: Front seats.
Information: Noise (rattling sound) when electric seat fore/aft adjustment is activated.
This is caused by an insufficiently greased plastic bushing on the shaft for seat fore/aft adjustment.
Action Required: In the event of a complaint, grease the plastic bushing.
Parts Info:
000.043.203.37 Grease, Castrol Optitemp LG2, 80g tube
... Tie-wrap (1 required, length approx. 15 cm), commercially available
Jumper lead (made in the workshop) consisting of:
... Wire (2 required, wire cross-section 2.5 mm Sq., length approx. 1 meter), commercially available
... Flat plug (2 required, 6.3-mm wide), commercially available
... Alligator clip (2 required, battery clamp), commercially available
Tools:
12-volt voltage source, e.g. afully charged vehicle battery
Slotted screwdriver (medium)
Small, clean syringe (2 or 10 ml sufficient), without a needle or Slotted screwdriver (small)
Jumper lead made in the workshop: Two wires, each with a cross-section of 2.5 mm Sq., approx. one meter long, with a 6.3-mm flat plug on one end and an alligator clip on the other end.
Work Procedure:
1. Move the front height adjustment of the seat to the top end position so that you have easy access to the plug connection on the seat control unit for carrying out subsequent work.
2. Remove front seat. Refer to Removing and installing front seat - section on "Removing".
NOTE: Make sure that the removed seat does not become damaged or soiled.
When carrying out subsequent work, carefully place the seat on a clean protective surface on the workbench as shown in Figure 1.
3. Carefully pry off the dust cap on the shaft of the seat fore/aft adjustment ( -item A- ) from the mounting using a slotted screwdriver and slide it towards the middle of the shaft.
4. At the front of the seat frame, press the trim for the control unit ( -item B- ) backwards at the bottom using a rotating movement ( -arrow- ) and then pull the trim down off the bracket.
5. At the front of the control unit, open the tie-wrap ( -arrow- ) for the wire connection and remove it.
6. Pull the wires up so that the connectors are easily accessible. Release the connector for seat fore/aft adjustment ( -item D- ) in the fourth slot from the right on both sides and pull it up off the control unit (-item C- ) to remove it.
An additional identifying feature of the connector is a blue marking with the inscription "LS" on the bushing tube of the wire to this connector ( -item E- ).
CAUTION: Voltage must not be applied to the narrow flat plug receptacles on the connector for seat fore/aft adjustment (Figure 6 - item H).
- This would damage the Hall sensor and disable the memory function.
- Only use 6.3-mm wide flat plugs on the lines for applying voltage to the connector for seat fore/aft adjustment.
7. Insert one wire of the workshop made jumper lead with the flat plug into each of the two 6.3-mm wide flat plug receptacles ( -item F and G- ) on the connector for seat fore/aft adjustment.
CAUTION: As soon as voltage is applied to the connector for seat fore/aft adjustment, the seat rail immediately starts moving.
- Danger of physical injury as a result of hands and arms being pinched and/or crushed or trapped and physical damage to adjacent objects.
- The servo motor can become damaged in the front or rear seat rail end position.
- Do not touch moving parts when the seat rail is moving.
- Make sure there is sufficient space around the seat rail.
- Quickly disconnect the connector for seat fore/aft adjustment from the voltage source in the front or rear seat rail end position.
8. If the wire in the flat plug receptacle -item F- is connected to the ground terminal and the line in the flat plug receptacle -item G- is connected to the positive terminal of the 12-volt voltage source, the seat rail will move backwards.
If the two wires at the 12-volt voltage source are reversed, the seat rail will move forward.
9. Check to see whether the plastic bushing ( -inset, item K- ) turns along with the shaft when the seat rail is moving.
NOTE: If the plastic bushing turns with the shaft (turns in the brake spring) continue with Step 10.
It is possible in some cases that the plastic bushing does not turn with the shaft. If this is the case continue with Step 16.
10. Move the seat rail backwards until the slit on the white plastic bushing ( -inset 1 and 2, item K- ) is easily accessible ( -inset 2, arrow- ).
NOTE: The seat rail must be stopped at the end of the backward direction of movement so that the slit in the plastic bushing is exposed and can therefore be thoroughly greased.
11. To grease the contact surface:
Fill the syringe with grease and use it to inject the grease into the slit (Figure 10 ) on the plastic bushing.
If you do not have a syringe, use a slotted screwdriver (small) to press grease into the slit on the plastic bushing a number of times until the slit is completely filled with grease.
12. Also use the syringe to apply grease to the top of the plastic bushing ( -item 1- ).
13. Move the seat rail forward.
The brake spring moves the plastic bushing up ( -arrow- ).
14. Use the syringe to apply grease to the bottom of the plastic bushing ( -item 2- ).
15. Repeat Steps 10 to 14 several times until the running surface of the spring is completely greased. End of remedial action. Continue with Step 20.
16. Move the seat rail backwards until the slit on the white plastic bushing ( -inset 1 and 2, item K- ) is easily accessible ( -inset 2, arrow- ).
NOTE: The seat rail must be stopped at the end of the backward direction of movement so that the slit in the plastic bushing is exposed and can therefore be thoroughly greased.
17. To grease the running surface:
Fill the syringe with grease and use it to inject the grease into the slit (Figure 14 ) on the plastic bushing.
If you do not have a syringe, use a slotted screwdriver (small) to press grease into the slit on the plastic bushing a number of times until the slit is completely filled with grease.
18. Move the seat rail forward.
19. Repeat Steps 16 to 18 several times until the running surface of the plastic bushing is completely greased. End of remedial action.
20. Slide the dust cap on the shaft for seat fore/aft adjustment over the mounting until the dust cap engages securely.
21. Before installing the seat in the vehicle, move the seat rail as described in Step 8 until the seat rail is centered with respect to the seat.
22. Pull flat plugs on the two lines out of the flat plug receptacles on the connector for seat fore/aft adjustment.
23. Plug connector for seat fore/aft adjustment into the control unit until the locking lugs engage securely.
24. Secure the wires to the control unit with a new tie-wrap.
25. Slide the trim with the locking lugs into the bracket on the seat frame until the locking lugs engage securely.
26. Install front seat. Refer to Removing and installing front seat - section on "Installing".
References:
Refer to Removing and installing front seat
996110, 996111, 996120, 996121, 996210, 996211, 996310, 996311, 996410, 996411, 996420, 996421, 996430, 996431, 996440, 996441, 996450, 996451, 996610, 996611, 996620, 996621, 996630, 996631, 996650, 996651, 996810, 996811, 996820, 996830, 996840, 996841, 996850, 996851
Model year as of 2002, Model year up to 2005 C02, C36