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Seat - Heating Element, Backrest And Cushion Replacement

Group
85

No.
701

Date
April 1989

THIS BULLETIN APPLIES TO THE U.S. AND CANADA REFERENCE: TP31127/1 (ENGLISH); BODY

The new seat heating element is not suitable for 740's or 760's prior to 1988. Some Modification is required to replace the element in earlier models.




Parts Block

For normal output element:
Thermostat P/N 3521779-3
Quantity 1


Replacement of backrest heating element




Remove storage pocket
Remove cushion (remove upholstery rails)

Remove:

- backrest adjuster cover (press out backwards using thin screwdriver)
- backrest adjusting mechanism covers on both sides
- lumbar support adjusting knob and guide


Remove clamps at bottom edge of upholstery

Pull away upholstery slightly and unhook clamps from center attachments at rear of seat.


High-output element (3-position switch):

Disconnect single-pole connector (SB).
Disconnect three-pole connector and push out pin on black (SB) lead.

Normal-output element (2-position switch):

Disconnect four-pole connector.
Push out pins on leads from backrest element.

New element

Cut leads as close as possible to connector.





Attach new pin, P/N 965824-6.

High-output element:

Fit new insulating sleeve, P/N 949583-9.

NOTE:
Sleeve may be attached to either pin.

Install new element and reconnect leads as before.


Normal-output element:

Cut leads as close as possible to element, leaving element in position. Install new element over original and reconnect leads (polarity unimportant).

Reassembly:

Replace upholstery and fit new clamps.


Reinstall

- lumbar Support guide and adjusting knob
- adjuster covers on both sides
- backrest adjuster


Normal-output element

Replace thermostat with new component, P/N 3521779-3.


Reinstall:

- seat cushion (ensuring upholstery rail is facing correctly)
- storage pocket at side of seat

Heating element in front seat cushion, replacement

Remove
- storage pocket

Removal

Remove upholstery rails and seat cushion.

High-output element

Disconnect single-pole connector (SB)
Disconnect three-pole connector arc push out black (SB) lead.

Normal-output element

Disconnect four-pole connector.
Push out round pins on seat cushion element leads.
Release clamps on either side
Pull off upholstery.


High-output element

Remove original heating element by releasing securing clamps.


Normal-output element

Cut leads as close as possible to element. Leave original element in position.

New element

Normal-output element




Cut leads as close as possible to connector.




Fit new pin, P/N 965824-6.

High-output element




Cut leads as close as possible to connector.




Fit new pins, P/N 965824-6 to red (R) and yellow-black (Y-SB) leads.

Fit pin, P/N 965822-0 to black (SB) lead.




Fit insulating sleeve, P/N 949584-7, to black (SB) lead.

High-output element




Transfer three-pole connector from original to new element.


Normal-output element

Transfer four-pole connector from original to new element.

Reassembly

Install new heating element

High-output element

Commence by securing element with adhesive tape. Stretch out element and fit clamps at appropriate points.

Normal-output element

Install new over original element.
Replace and secure upholstery with new clamps
Replace seat cushion
Reconnect leads. Ensure upholstery rails are facing correctly.

During the New Car Warranty period, repairs required due to defects in workmanship or material only must be submitted under:


Operation # Labor Description Time Allowance

852713 Cushion heater pad, replace-left 0.9 hr.
852714 Cushion heater pad, replace-right 0.9 hr.
852723 Backrest heater pad, replace-left 0.9 hr.
852724 Backrest heater pad, replace-right 0.9 hr.