G. Adjustment of Fifth Bow Latch Motor

On some cars, the fifth bow latch motor may jam when the top is raised or lowered. As a result, the top cannot be operated by means of the ROOF switch and the Tonneau cover flaps may be broken off by the fifth bow.

To avoid this happening, adjustment of the locking rods is necessary. In addition, an extra locking washer should be fitted on the locking rods to ensure that they are securely mounted. The object is to make sure the latches, rather than the rack teeth, stop the motor travel.

Parts:

Lock washer (2) 94 41 221

Action:

Checking operation;

1. Operate the top so that it is fully raised and the fifth bow and the Tonneau cover are standing vertical. The Tonneau cover's access flaps should be fully closed.

2. Remove the covering shell and check that the screws for the locking motor and locking mechanism for the fifth bow are tightened down hard.

Tightening torque: 88.8 in.lbs. (10 Nm)





3. Using a 1 mm feeler gauge, check that there is a clearance between the last cogwheel tooth and the smooth part of the upper and lower toothed segments. See Figure 11, point 3.

If there is no clearance, proceed to point 4.

Adjustment:

In the event of incorrect clearance, both sides will have to be adjusted.





4. Remove the locking rods. The easiest way to do this is by operating the fifth bow's latch motor to the halfway open position (flaps at 45°) by means of the ISAT, using commands:

"TSAS"
"ACTIVATE"
"5TH BOW LATCH MOTOR"
"UP"

Important
On VIN Serial Nos. below S7015157, this cannot be done unless you have previously changed the ECM as described in PSI 03/95-0554.

5. Operate the fifth bow's latch motor one complete cycle by means of ISAT, using commands:

"TSAS"
"ACTIVATE
"FIFTH BOW LATCH MOTOR"
"DOWN"

Check that the latch motor is in the fully locked position.

6. Remove and discard all locknuts (if fitted) on the locking rod clevis'. Later cars do not have any lock nuts.

7. Adjust the locking rods inward toward the motor until it is just possible to fit them in the holes in the motor's locking arms.

8. Then screw in the locking rods five turns so that they are slightly too short. It might be necessary to cut a few extra threads on the locking rods. In that case, use an M5 die.

9. Operate the fifth bow's latch motor to the halfway open position by means of ISAT, using commands:

"TSAS"
"ACTIVATE"
"5TH BOW LATCH MOTOR"
"UP"

Fit the locking rods. Leave the old circlip in place and fit lock washers, P/N 94 41 221.

10. Operate the fifth bow's latch motor to the closed position by means of ISAT using commands:

"TSAS"
"ACTIVATE"
"5TH BOW LATCH MOTOR"
"DOWN"

Go back to point 3 and check again.

11. Operate the fifth bow's latch motor to the open position by means of ISAT, using commands:

"TSAS"
"ACTIVATE"
"5TH BOW LATCH MOTOR"
"UP"

Stand behind the car and look through the holes for the fifth bow's latches. A maximum of 1.5 mm of the latch lug should be visible in each hole.





12. If more than 1.5 mm of the latch lugs can be seen, go back to point 5 and extend the locking rods slightly. The important thing, however, is to make sure that the clearance as described in point 3 is present.

If points 3 and 12 cannot be carried out at the same time, the fifth bow's latch fittings will have to be adjusted as described under "Adjustment" on page 133 in Service Manual 8:5 Cabriolet.

13. End SAT communication and clear the diagnostic trouble codes (DTC's).

14. Fit the covering shell.

15. Operate the top and check that it works properly.