Windshield Wiper Testing and Adjustment Tools

Frequently Asked Questions About Windshield Wiper Testing and Adjustment Tools

Poor wiping performance can have various causes. In addition to the wiper blade, the condition of the windshield, and the wiper motor, the wiper arm angle and contact pressure can also play a role. The following questions will help you distinguish between angle inspection, adjustment, and force measurement, and select the appropriate tool.

• What windshield wiper testing tools does Leitenberger offer?

  Two different sets of tools are available for the mechanical testing of windshield wiper arms:

  AWPE 03 and AWPE 04
  → Check the angle of the wiper arm and adjust it if necessary.

  DKM 15 and DKM 45
  → Measure the contact force of the wiper arm.

  The methods complement each other but examine different characteristics of the wiper system.

• What could be the causes of poor cleaning results?

  Possible causes include, for example:

  • worn or damaged wiper blades,
  • a dirty or damaged windshield,
  • an improper wiper arm angle,
  • insufficient or excessive contact pressure,
  • a damaged wiper arm,
  • mechanical play,
  • problems with the wiper drive.

  Therefore, if the problem persists, you should not automatically assume that only the wiper blade needs to be replaced.

• What does the wiper arm angle mean?

  This refers to the position of the wiper blade holder or the wiper arm relative to the front or rear windshield.
  
  In suitable wiper systems, the wiper blade holder must be positioned at a specific angle relative to the windshield surface so that the wiper blade operates correctly during movement.

• What symptoms might indicate that the wiper arm is at the wrong angle?

  Leitenberger specifically mentions:

  • rattling,
  • scraping,
  • squeaking,
  • poor wiping performance,
  • and uneven wiping performance

  as typical reasons for conducting an angular inspection.

• Does a rattling windshield wiper automatically mean that the angle is wrong?

  No.

  Rattling can also have other causes, such as:

  • a worn wiper blade,
  • a dirty windshield,
  • an unsuitable wiper blade surface,
  • mechanical play,
  • uneven contact pressure.

  Angle measurement is therefore part of the troubleshooting process and does not automatically prove the cause of the problem.

• What is AWPE?

  AWPE stands for the Leitenberg testing and adjustment system for corresponding windshield wiper arms.

  The system can be used to:

  1. measure the angle of the wiper blade mount and
  2. adjust it when appropriate.

  Various mounts, adapters, and adjustment tools are available for this purpose.

• What is the difference between AWPE 03 and AWPE 04?

  AWPE 03 is the basic kit.

  It includes:

  • AWPE-WE angle measuring unit,
  • AWPEA-B wiper blade holder,
  • two AWPEE-Z4 adjustment tools.

  AWPE 04 expands this kit to include the following additional items:

  • AWPEA-C,
  • two M5 lever mounts,
  • two M6 lever mounts,
  • two M8 lever mounts.
• When is AWPE 03 appropriate?

  AWPE 03 is suitable as a starter kit if the included wiper blade holder and adjustment tools cover the vehicles you service regularly.
  
  The system can be expanded later with additional available holders and adjustment tools.

• When is AWPE 04 appropriate?

  AWPE 04 is particularly useful for repair shops that service a wide range of vehicles and wiper arms.
  
  With its additional wiper blade mount and M5, M6, and M8 lever mounts, the set offers more customization options right out of the box.

• Can AWPE 03 be expanded later?

  Yes.

  Leitenberger offers various mounts and adjustment tools separately.

  These include, for example:

  • AWPEA-B
  • AWPEA-C
  • AWPEA-D
  • AWPEE-Z4
  • AWPEE-TU
  • AWPEE-XY
  • AWPE-M5
  • AWPE-M6
  • AWPE-M8.
• Is AWPE 04 just another measuring device?

  No.

  The unit of angle measurement is essentially the same.

  The main difference lies in the AWPE 04's more extensive mechanical features and additional mounting options.

• Does the wiper blade need to be removed to measure the angle?

  Yes.
  
  In the AWPE application described, the wiper blade is removed. The appropriate adapter is then attached to the wiper arm and connected to the angle measurement unit.

• How is the wiper arm angle measured?

  In simple terms, the inspection is carried out in several steps:

  1. Remove the wiper blade.
  2. Insert the appropriate wiper arm adapter.
  3. Install the angle measuring unit.
  4. Determine the angle position.
  5. Compare the measured value with the specified reference value.

  It is crucial that the correct adapter be used for the respective wiper arm.

• Can the angle be adjusted directly using AWPE?

  Yes.
  
  In addition to angle measurement, the system includes the necessary adjustment tools.
  
  Leitenberger describes the design such that one tool is used for adjustment and a second as a counterholder. This allows for controlled adjustment.

• Why are two tools used during setup?

  In the bracketless wiper systems described, the corrective force should not simply be applied via the wiper blade mount itself.

  That is why the AWPE system uses:

  • an adjustment tool and
  • a counterholder.

  This allows for more precise adjustment of the wiper arm.

• Can the angle be monitored at the same time as the adjustment is being made?

  Yes.
  
  The AWPE system is designed so that angle measurement and angle adjustment can be performed simultaneously or under direct control.

• Can a wiper arm simply be bent with pliers?

  Uncontrolled deformation of the wiper arm is not recommended.
  
  When making an intended angle adjustment, force should be applied at the appropriate points using the correct adjustment tool.
  
  The AWPE system uses an adjustment tool and a counterholder for this purpose.

• Can every wiper arm be adjusted using AWPE?

  Not automatically.

  The following factors are crucial:

  • the design of the wiper arm,
  • the existing mounting point,
  • a compatible adapter,
  • manufacturer specifications,
  • and the available adjustment options.

  Therefore, you should check the vehicle and adapter compatibility before use.

• Is AWPE only compatible with Bosch Aerotwin?

  No.

  The Leitenberger documents list blade-less wiper systems from various manufacturers, including, for example, Bosch, Valeo, and SWF.

  However, I would not maintain a fixed list of brands for the specific vehicle coverage in this category. The determining factor is the corresponding wiper arm mount or adapter.

• Is a “flat blade” the same as a traditional wiper blade?

  No.
  
  In modern frameless or flat-blade wipers, the spring and pressure distribution are designed differently than in classic wiper blades with a frame structure.
  
  However, when selecting an AWPE, the specific wiper arm and mounting geometry are more important than the marketing name.

• Should the wiper arm angle be checked after replacing the windshield?

  It may be a good idea to have the wipers inspected after replacing the front or rear windshield, especially if:

  • the wiper arm was removed,
  • the installation configuration has changed,
  • rattling or scraping occurs afterward,
  • the wiping performance is no longer even,
  • the vehicle manufacturer specifies a corresponding inspection.
• Can a new windshield affect the wiper arm angle?

  A change in the windshield’s position or installation configuration can affect the geometric relationship between the wiper arm, the wiper blade, and the windshield.
  
  Therefore, it may be advisable to check the angle after windshield work if symptoms indicate a problem or if the manufacturer’s specifications require it.

• Should the angle also be checked on rear windshield wipers?

  Leitenberger describes the AWPE system in terms of its angular relationship to the front and rear windows.
  
  Whether a specific rear wiper application is supported, however, depends on the wiper arm and the available mounting bracket.

• What does “contact pressure” mean in the context of windshield wipers?

  The contact force describes the force with which the wiper arm presses the wiper blade against the windshield.

  It is measured in Newtons (N).

• Why is contact pressure important?

  If the force is not correct, the wiper blade may not make even contact with the windshield.

  This can lead to, for example:

  • poor cleaning,
  • uneven wiping,
  • the blade lifting off in certain areas,
  • rattling, or other issues.
• How can the contact pressure of the wiper arm be measured?

  For this purpose, Leitenberger offers the DKM 15 and DKM 45 electronic force measurement devices.

  The highly sensitive force sensor is mounted on the wiper arm according to the intended measurement method and records the force exerted.

• What is DKM 15?

  The DKM 15 is an electronic force gauge for testing the contact force of windshield wiper arms.

  Technical Specifications:

  • Measuring range: 0–15 N
  • Accuracy: ±1% FS
  • 10 measurements per second
  • Automatic storage of the maximum value
  • 9-V block battery
  • Sensor: 40 × 12 × 15 mm.
• What is DKM 45?

  The DKM 45 operates on the same basic principle but has a wider measurement range:

  • Measurement range: 0–45 N
  • Accuracy: ±1% FS
  • 10 measurements per second
  • Automatic storage of the maximum value
  • 9-V block battery
  • Sensor: 40 × 12 × 15 mm.
• What is the difference between the DKM 15 and the DKM 45?

  The most important difference is the measurement range:

  DKM 15: 0–15 N
  DKM 45: 0–45 N.

  The selection should therefore be based on the expected contact force or the force specified by the manufacturer.

• Which device is more accurate—the DKM 15 or the DKM 45?

  Both product pages specify an accuracy of ±1% of the full-scale (FS) value.

  Since the measurement ranges differ, it is important to consider not only the maximum measured value but also the actual measurement range required when making a selection.

• What does ±1% FS mean?

  FS stands for Full Scale, which is the maximum value of the measurement range.

  When the accuracy is specified as ±1% FS, the specified accuracy refers to the maximum measurement range of the respective device and not to every single current measurement value.

• Do the DKM 15 and DKM 45 have the same sensor?

  The currently specified sensor dimensions are identical for both devices:

  40 × 12 × 15 mm.
  
  Both use a symmetrically designed force sensor.

• What is the advantage of a symmetrical force sensor?

  According to Leitenberger, the top and bottom surfaces of the sensor have the same sensitivity.
  
  As a result, it does not matter which of the two sensor surfaces is used to sense the force during measurement.

• How fast do the DKM 15 and DKM 45 measure?

  According to the product description, both devices perform 10 measurements per second.

• Do the force gauges store a measurement value?

  Yes.

  The DKM 15 and DKM 45 automatically store the maximum value.

  This makes it easier to read the value when the highest reading occurs only briefly during the actual measurement.

• Are measurement curves saved?

  The current product pages do not describe a continuous data-logging or measurement-curve function.
  
  The devices store the maximum value but are not specified as data loggers.

• Do the DKM 15 and DKM 45 need to be connected to the vehicle?

  No.

  Power is supplied by a 9-V block battery in each case.

• Are the devices delivered calibrated?

  Yes.

  The scope of delivery includes:

  • for the DKM 15, a factory calibration certificate WKZ_DKM 15
  • for the DKM 45, a factory calibration certificate WKZ_DKM 45.
• Is there a universal target value for the contact pressure of a windshield wiper arm?

  No.
  
  The relevant manufacturer or repair specifications are decisive for evaluating a specific vehicle.

• Does a contact force of less than 10 N automatically mean that the wiper arm is defective?

  No.

  The assessment must be based on the vehicle-specific target value. Only if the measured force falls outside the specified range should the spring, wiper arm, or other mechanical causes be investigated further.

• Can you easily increase the contact pressure by bending the wiper arm?

  The contact pressure is largely determined by the design or spring mechanism of the wiper arm.
  
  Repairs or adjustments must be performed in accordance with the design and the manufacturer's specifications.

• Is the wiper arm angle the same as the contact pressure?

  No.

  These are two completely different quantities.

  Wiper arm angle
  → the geometric position of the wiper blade relative to the windshield.

  Contact force
  → the force with which the wiper blade is pressed against the windshield.

  That is why AWPE and DKM can complement each other.

• Can the angle be correct but the contact force still be wrong?

  Yes.
  
  A wiper arm can be positioned geometrically correctly, while, for example, the spring force is noticeably off.
  
  Conversely, the contact pressure may be correct, while the angle of the wiper blade mount is incorrect.

• Which test should be performed first in cases of rattle?

  First, the simpler causes should be checked:

  • Condition of the wiper blade,
  • cleanliness of the windshield,
  • visible damage,
  • mechanical condition of the wiper arm.

  If the problem persists, the following can then be

  1. specifically examined: wiper arm angle using AWPE
  2. and contact pressure using DKM.
• Does a new wiper blade need to be checked first before adjusting the wiper arm?

  Yes, the condition of the wiper blade should be taken into account in the diagnosis.
  
  A worn, dirty, or unsuitable wiper blade can also cause poor wiping performance.
  
  Angle adjustment should not be performed based on suspicion alone.

• Can a windshield wiper problem be caused by a dirty windshield?

  Yes.
  
  Oil, wax, silicone, or other residues can alter the friction characteristics between the wiper blade and the windshield.
  
  Therefore, the windshield should be included in the diagnosis before making any mechanical adjustments.

• Can a wiper arm become misaligned after an accident or repair?

  Mechanical stress or work performed near the windshield or the wiper system can affect the position of the wiper arm.
  
  If such symptoms occur, it may therefore be advisable to check the angle and, if necessary, the force.

• Can an incorrectly installed wiper arm cause poor wiping performance?

  Yes.

  In addition to contact pressure and angle, the following factors can also influence wiping performance:

  • initial position,
  • installation orientation,
  • and connection to the wiper shaft.

  Therefore, the AWPE angle measurement does not replace a check of the entire wiper mechanism.

• Can AWPE and DKM also be used with rear window wipers?

  In general, testing is also possible on rear wiper systems if:

  • the appropriate tool or sensor can be used,
  • a suitable mounting is available,
  • and the manufacturer’s specifications permit it.

  The specific application must be tested on the respective wiper system.

• Do AWPE and DKM replace the diagnosis of the wiper motor?

  No.

  The tools test the mechanical properties of the wiper arm.

  Faults in:

  • the wiper motor,
  • the linkage,
  • the electrical system,
  • the control system,
  • and the end position

  must be examined separately.

  For electrical measurements, for example, automotive test lamps and multifunction testers as well as multimeters for automotive and commercial vehicle workshops are available.

• What equipment is recommended for a repair shop that regularly replaces windshields?

  For such work, a combination of:

  • the AWPE angle measurement and adjustment tool,
  • compatible wiper arm mounts,
  • and the DKM force gauge

  may be useful.

  This allows for a precise assessment of both the geometric position and the contact force.

• Which model is best suited for a multi-brand repair shop?

  For a repair shop that services various vehicle brands, AWPE 04 offers greater flexibility thanks to its more comprehensive standard equipment.

  Additional vehicle- or wiper arm-specific mounts and adjustment tools can be added as needed.

  When measuring force, the required measurement range should determine whether DKM 15 or DKM 45 is used.

• Are AWPE and DKM intended only for passenger cars?

  Specific suitability depends on:

  • wiper arm design,
  • required adapter,
  • measuring range,
  • manufacturer's specifications.
• What should be checked after adjusting the wiper arm?

  After making the proper adjustment, the wiper system’s operation should be checked again.

  Depending on the application, this includes:

  • wiping pattern,
  • noise level,
  • smooth movement,
  • parking position,
  • contact with the windshield.

  If necessary, the angle can then be measured again.

• Where can I find more tools for vehicle maintenance?

  You can find additional cross-system installation, testing, and leak detection tools under Practical Specialty Tools for the Workshop.

  Tools for backup cameras, parking sensors, and anti-pinch systems can be found under Testing and Service Tools for Driver Assistance and Safety Systems.

  All parent tool groups can be found under Specialty Tools for Workshops and Service.