Part 3
WM 449503 Suspension alignment, complete
Adjusting front axle toe
WARNING
Steering-angle sensor not calibrated or calibrated incorrectly
- Unexpected vehicle handling
- Steering-angle sensor does not function
- Malfunction in steering-angle sensor
-> After working on wheel suspension parts, when replacing the steering-angle sensor and after changing the wheel alignment values, calibrate the steering-angle sensor using PIWIS Tester II 9818.
-> Keep the front wheels in straight-ahead position on the measuring platform during calibration.
-> On vehicles with electromechanical steering, also re-teach the electric steering lock settings.
WARNING
Steering-angle sensor not calibrated or calibrated incorrectly
- Unexpected vehicle handling
- Steering-angle sensor does not function
- Malfunction in steering-angle sensor
-> After working on wheel suspension parts, when replacing the steering-angle sensor and after changing the wheel alignment values, calibrate the steering-angle sensor using PIWIS Tester II 9818.
-> Keep the front wheels in straight-ahead position on the measuring platform during calibration.
-> On vehicles with electromechanical steering, also re-teach the electric steering lock settings.
WARNING
Steering-angle sensor not calibrated or calibrated incorrectly
- Unexpected vehicle handling
- Steering-angle sensor does not function
- Malfunction in steering-angle sensor
-> After working on wheel suspension parts, when replacing the steering-angle sensor and after changing the wheel alignment values, calibrate the steering-angle sensor using PIWIS Tester II 9818.
-> Keep the front wheels in straight-ahead position on the measuring platform during calibration.
-> On vehicles with electromechanical steering, also re-teach the electric steering lock settings.
WARNING
Steering-angle sensor not calibrated or calibrated incorrectly
- Unexpected vehicle handling
- Steering-angle sensor does not function
- Malfunction in steering-angle sensor
-> After working on wheel suspension parts, when replacing the steering-angle sensor and after changing the wheel alignment values, calibrate the steering-angle sensor using PIWIS Tester II 9818.
-> Keep the front wheels in straight-ahead position on the measuring platform during calibration.
-> On vehicles with electromechanical steering, also re-teach the electric steering lock settings.
WARNING
Steering-angle sensor not calibrated or calibrated incorrectly
- Unexpected vehicle handling
- Steering-angle sensor does not function
- Malfunction in steering-angle sensor
-> After working on wheel suspension parts, when replacing the steering-angle sensor and after changing the wheel alignment values, calibrate the steering-angle sensor using PIWIS Tester II 9818.
-> Keep the front wheels in straight-ahead position on the measuring platform during calibration.
-> On vehicles with electromechanical steering, also re-teach the electric steering lock settings.
WARNING
Steering-angle sensor not calibrated or calibrated incorrectly
- Unexpected vehicle handling
- Steering-angle sensor does not function
- Malfunction in steering-angle sensor
-> After working on wheel suspension parts, when replacing the steering-angle sensor and after changing the wheel alignment values, calibrate the steering-angle sensor using PIWIS Tester II 9818.
-> Keep the front wheels in straight-ahead position on the measuring platform during calibration.
-> On vehicles with electromechanical steering, also re-teach the electric steering lock settings.
WARNING
Steering-angle sensor not calibrated or calibrated incorrectly
- Unexpected vehicle handling
- Steering-angle sensor does not function
- Malfunction in steering-angle sensor
-> After working on wheel suspension parts, when replacing the steering-angle sensor and after changing the wheel alignment values, calibrate the steering-angle sensor using PIWIS Tester II 9818.
-> Keep the front wheels in straight-ahead position on the measuring platform during calibration.
-> On vehicles with electromechanical steering, also re-teach the electric steering lock settings.
The steering-angle sensor must be calibrated if the previous wheel alignment values (on rear and/or front axle) were changed.
Tighten lock nut on tie rod at -C- to 70 Nm (52 ftlb.) in conjunction with accessory for torque wrench: Open-jawed wrench insert a/f 22 Nr.95.
Open-jawed wrench insert, a/f 22
If the specified tightening torque has not been reached after alignment on the alignment platform (due to reasons of space), turn the steering to left and right and tighten the tie rod screws. Counter with open-ended wrench.
The toe is adjusted at the tie rod threaded joint for the tie rod/tie rod ball (ball joint) -C-.
Toe adjustment -C-
Preliminary work:
1. Check whether the steering wheel is displaced with respect to the steering gear.
2. To do this, centre the steering gear as described below.
3. Turn wheels to the straight-ahead position.
4. Remove cover for underbody (transmission protection) and heat shield from the steering -arrows-.
Heat shield/steering attachment
5. The steering centre position marking -1- is under the heat shield at the front in the direction of travel on the steering gear housing (shown here looking in the direction of travel on a removed unit for clarity).
Steering centre position marking
No. -2- is the remains of the desired breaking point from the locking pin on new steering gears. This locks the steering gear in the centre position. After installation of a new steering gear, the lower part of the pin is sheared off at the desired breaking point by turning the steering wheel.
6. Afterwards, adjust front wheel alignment if necessary until marking on steering housing (triangle) is aligned with the marking lug -1- of the driver.
If necessary, reposition the steering wheel => 481019 Removing and installing steering wheel. When repositioning the steering wheel, try to get the best position.
WARNING
Incorrect handling of airbag units
- Triggering of airbag unit
- System faults can occur
-> Switch off ignition and remove ignition key or remote control (hand-held transmitter).
-> A voltage supply (e.g. battery charger) must not be connected to the external power supply/jump-lead starting terminals.
-> Disconnect the battery and insulate the ground strap so that all contact with a ground carrier is avoided.
-> Wait 1 minute after disconnecting the battery.
-> Only detach connector on the triggering unit after the waiting time has elapsed.
-> Make sure that no foreign objects are located in front of the airbag unit during installation.
-> Replace damaged parts during removal.
-> Always position airbag units so that the blow-out opening is facing upwards, e.g. crest on driver's airbag.
-> Do not position anything on the airbag units.
-> If removed for an extended period, the airbag units must be stored in a safe place.
-> Airbag units must not come into contact with grease, oil, detergents, liquids, or similar substances.
-> Do not expose airbag units to temperatures above 90°.
-> Do not remove the short-circuit spring on the plug-in contacts.
-> Ignition and preparations may only be carried out by skilled staff, supervised by a second responsible person.
-> Before disposal, the airbag unit must be rendered harmless by electrical ignition performed in accordance with all precautionary measures, thereby preventing it from being used incorrectly.
7. Clamp steering wheel in centre position with steering wheel holder.
Steering wheel holder
Information
- Use only steering wheel holders -A- that do not project into the area of the airbag unit -B-.
- If necessary, shorten guiding rod at the top -arrow-.
Steering-wheel holder (example shown)
8. Adjust toe at hexagon of tie rod(s) after releasing lock nut(s). The steering-angle sensor must subsequently be calibrated by PSM.
WARNING
Steering-angle sensor not calibrated or calibrated incorrectly
- Unexpected vehicle handling
- Steering-angle sensor does not function
- Malfunction in steering-angle sensor
-> After working on wheel suspension parts, when replacing the steering-angle sensor and after changing the wheel alignment values, calibrate the steering-angle sensor using PIWIS Tester II 9818.
-> Keep the front wheels in straight-ahead position on the measuring platform during calibration.
-> On vehicles with electromechanical steering, also re-teach the electric steering lock settings.
WARNING
Steering-angle sensor not calibrated or calibrated incorrectly
- Unexpected vehicle handling
- Steering-angle sensor does not function
- Malfunction in steering-angle sensor
-> After working on wheel suspension parts, when replacing the steering-angle sensor and after changing the wheel alignment values, calibrate the steering-angle sensor using PIWIS Tester II 9818.
-> Keep the front wheels in straight-ahead position on the measuring platform during calibration.
-> On vehicles with electromechanical steering, also re-teach the electric steering lock settings.
WARNING
Steering-angle sensor not calibrated or calibrated incorrectly
- Unexpected vehicle handling
- Steering-angle sensor does not function
- Malfunction in steering-angle sensor
-> After working on wheel suspension parts, when replacing the steering-angle sensor and after changing the wheel alignment values, calibrate the steering-angle sensor using PIWIS Tester II 9818.
-> Keep the front wheels in straight-ahead position on the measuring platform during calibration.
-> On vehicles with electromechanical steering, also re-teach the electric steering lock settings.
WARNING
Steering-angle sensor not calibrated or calibrated incorrectly
- Unexpected vehicle handling
- Steering-angle sensor does not function
- Malfunction in steering-angle sensor
-> After working on wheel suspension parts, when replacing the steering-angle sensor and after changing the wheel alignment values, calibrate the steering-angle sensor using PIWIS Tester II 9818.
-> Keep the front wheels in straight-ahead position on the measuring platform during calibration.
-> On vehicles with electromechanical steering, also re-teach the electric steering lock settings.
WARNING
Steering-angle sensor not calibrated or calibrated incorrectly
- Unexpected vehicle handling
- Steering-angle sensor does not function
- Malfunction in steering-angle sensor
-> After working on wheel suspension parts, when replacing the steering-angle sensor and after changing the wheel alignment values, calibrate the steering-angle sensor using PIWIS Tester II 9818.
-> Keep the front wheels in straight-ahead position on the measuring platform during calibration.
-> On vehicles with electromechanical steering, also re-teach the electric steering lock settings.
WARNING
Steering-angle sensor not calibrated or calibrated incorrectly
- Unexpected vehicle handling
- Steering-angle sensor does not function
- Malfunction in steering-angle sensor
-> After working on wheel suspension parts, when replacing the steering-angle sensor and after changing the wheel alignment values, calibrate the steering-angle sensor using PIWIS Tester II 9818.
-> Keep the front wheels in straight-ahead position on the measuring platform during calibration.
-> On vehicles with electromechanical steering, also re-teach the electric steering lock settings.
WARNING
Steering-angle sensor not calibrated or calibrated incorrectly
- Unexpected vehicle handling
- Steering-angle sensor does not function
- Malfunction in steering-angle sensor
-> After working on wheel suspension parts, when replacing the steering-angle sensor and after changing the wheel alignment values, calibrate the steering-angle sensor using PIWIS Tester II 9818.
-> Keep the front wheels in straight-ahead position on the measuring platform during calibration.
-> On vehicles with electromechanical steering, also re-teach the electric steering lock settings.
Specified tightening torque of lock nut(s) -C- = 70 Nm (52 ftlb.).
Toe adjustment -C-
Front-axle toe-difference angle
The toe-difference angle is not adjustable.