These suggestions and solutions for technical problems are from service bulletins and other information published by Mercedes-Benz, selected and adapted for independent repair shops.

Modification of Special Tool for Pulling Axle Halfshaft with Double-Row Tapered Roller Bearings on Models 124.090/092/193/290

These models have a rear axle halfshaft with double-row tapered roller bearings. These bearings can only be pressed out of the rear halfshaft flange with the wheel carrier removed from the vehicle, then by the use of a stationary hydraulic press.

These bearings require an extraction force three times that required to pull the double row ball bearings used on other models. The regular M-B puller (Special Tool number W202 589 04 43 00) is not designed to handle such forces.  As a result, the removal of rear axle half shafts with the double-row tapered roller bearings is not possible.

The special tool puller must be modified with a shear pin, which is installed at the pressure screw of the hydraulic press. The shear pin will shear at a force of 40 Nm, thus preventing any further pressure build-up at the hydraulic press and making the operation (except on Model 124.090/092/193/290) safer (the pin will shear). The modified pressure screw is available with the shear pin as a spare part under Special Tool Part Number W202 589 04 43 11.

Note:  Review the following document in WIS: AR35.20-P-0130B.

Implausible Oil Level Display on ML with M112 or 113 Engine

If the engine oil level is actually okay, but the instrument cluster is displaying Oil Level Below Min, Oil Level Above Max, or Engine Oil Level – Visit Workshop, perform the following steps:

1. Check if the engine has the appropriate oil dipstick. Correct oil dipstick if necessary.
2. Check if the oil level is correct using the proper oil dipstick. Correct oil level if necessary.
3. Check if correct oil data is stored in the instrument cluster as follows:
   1. Hook up DAS
   2. Select vehicle mode
   3. Select instrument cluster. If the oil data is incorrect, change oil data in the instrument cluster by performing steps d. to g.
   4. Select control unit settings
   5. Select coding or variant coding
   6. Select engine or engine variant
   7. Save data
4. Check for DTCs. If an oil level sensor fault code has been stored, perform the following

steps:

• If three fault codes (P2039, P2040, P2041) are present, the oil level sensor connector is incorrectly plugged in, the wiring harness is damaged (short circuit), or the oil level sensor is defective.
• If one or two of the above mentioned fault codes are stored, replace the oil level sensor.

Brake or Tail Lamp Lights Permanently On, Trunk Illumination Inoperative

Models203.040/061/064/065/076/081/084/261/264/281/284/740/747/764

If you get a complaint in the above model vehicles that the brake or tail lamp lights are permanently on even though the lights are switched off and the light menu in the instrument cluster is set to “Manual,” or the trunk illumination is inoperative, the output transistor in the rear SAM (N10/2) may be inoperative. Typically, there will be no DTCs, no message in the instrument cluster and no light will be substituted. The condition must be confirmed prior to repairing the vehicle. To resolve, replace the rear SAM, Part Number A203 545 32 01.

Failed State OBD Test, 1993 Through 1996 With LH-SFI or HFM-SFI

It has come to the attention of Mercedes-Benz USA that these Mercedes-Benz vehicles have inadvertently failed OBD Inspection/Maintenance tests in certain states conducting OBD checks. These failures are due to problems in state guidelines, which were established without the knowledge of how specific Mercedes-Benz systems operate.

Testing guidelines read as follows for states that test using the OBD system.  Vehicles fail the entire OBD inspection if they fail either of the following criteria:

• Malfunction indicator lamp (MIL) is illuminated with the vehicle in the key-on/ engine-running condition.
• MIL is illuminated after the vehicle is started, even if no fault codes are present, which could indicate a serial data link failure.

Please be advised, that certain Mercedes-Benz vehicles will illuminate the MIL during DTC read-out and while the tool is connected, regardless of whether or not any faults are present in the OBD system.  This feature was designed into Mercedes-Benz vehicles equipped with LH-SFI and HFM-SFI control modules during the early phase of OBD so that the technician would know when a scan tool is properly communicating (“linked-up”) with the control module. For this reason, these vehicles should not failed any state inspection. Furthermore, it is critical to note that this is only a “visual illumination.”  The MIL is not “commanded on” and bit Mode $ 01, P1D $ 01, Data A, bit 7 is not set or activated in the OBD software.

DTC B1000 in Electronic Ignition Switch on Model 203

Due to an error in the DTC software, it is possible that Code B1000 may be recorded in the Electronic Ignition Switch (EIS, N73). If this fault is present, but not current, the DTC may be ignored and the DTC memory erased. Do not replace the EIS for this condition.