Mercedes Transmission Service Repair And Computer Diagnosis Serving Rockville, Gaithersburg And Laurel, Columbia Maryland MD

Mercedes Transmission Service Repair And Computer Diagnosis Serving Rockville, Gaithersburg And Laurel, Columbia Maryland MD

The majority of Mercedes Benz cars and SUVs coming into our shop for transmission repair service have the 722.6 automatic transmissions. These transmissions utilize 5 forward speeds and are fully computer-controlled and utilize adaptive shift learning.The earlier transmissions were prone to major gear train failure, resulting in a mess of damaged internal components. The most noticeable symptoms of gear train failure are loss of movement in forward or reverse and/or whining or grinding sounds when engaged in gear. The sounds can occur with or without vehicle movement. Gear train failures have been greatly reduced in later model transmissions due to a design change. The gear shift selector located in the center console of Mercedes Benz automobiles is coupled with a complex switch that sends electrical signals to the transmission computer controller. This switch is not adequately protected against conductive water based liquids that may enter through the center console area.

Spilling your favorite beverage or leaving the sunroof open during a cloudburst can ruin the TRRS shifter switch, usually resulting in transmission malfunctions. This occurs because unlike oil based liquids and materials which do an adequate job of insulating electrical current, water based liquids are highly conductive. This is why the insulation on electrical wires is made of plastic, a petroleum oil based material. The TRRS switch cannot be repaired or bypassed, so replacing the switch will is required to restore proper function, allowing the correct signals to reach the Mercedes transmission computer controller through the wiring harness. All 722.6 Mercedes transmissions experience many electronic problems; however, there are major differences between the earlier and later 722.6 transmission models. These differences play a big role in the probability of cause of failure as well as the cost of repair. Electronic problems are still very prevalent even in the late model units, but these issues are relatively inexpensive to repair, because they can be addressed without removing and disassembling the transmission. The three electronic problems mentioned below account for 85% of the electronic problems we see in Mercedes-Benz transmissions.

A defective transmission conductor plate is generally diagnosed by the speed sensor codes it produces when it has failed. This conductor plate is located on top of the transmission valve body, which can be accessed from under the vehicle. Repair of this component is not feasible, so the part must be replaced with a new one produced by the manufacturer, available from the Mercedes dealership. The replacement of the conductor plate requires removal of the transmission valve body. When the valve body is removed, the conductor plug must also be removed, and should always be replaced with a new one. The conductor plug often leaks fluid to the external wiring harness which is attached to it. When this occurs, the leaking fluid can get drawn up through the wiring harness and can accumulate in the transmission control module. This is called wicking action, like a wick for an oil lantern. Oils, including transmission fluid, are not good conductors of electricity; however they can wreak havoc when introduced into sensitive electronic equipment, such as microprocessors. To correct this problem, the conductor plug must be replaced, the wiring harness must be cleaned of excess transmission fluid, and the transmission control module should be disassembled and sprayed clean with electrical contact cleaner. In most cases the transmission control module will revert back to proper operation, but in some cases it must be replaced.

But Mercedes has grown the new C-Class, with an 80mm increase in the wheelbase compared with the previous model, and a 95mm increase in overall length. It鈥檚 also 40mm wider, resulting in a more spacious interior. One difference with the hybrid installation is the location of the battery pack - rather than under the bonnet, as in the E-Class, it鈥檚 below the boot floor, in the spare wheel well. This doesn鈥檛 compromise the car鈥檚 load carrying ability - indeed, boot space on the new C-Class is a very acceptable 480 litres. And it looks the part too. Mercedes has effectively created a miniature version of the new S-Class - the new C-Class follows the flagship鈥檚 lines, with elegant side creases tapering together toward the rear of the car, creating a very different, more confident-looking car. Whereas the current C-Class seemed to be trying very hard to match its rivals, the new one aspires to being nothing other than a Mercedes.

We had a brief drive of the C300 BlueTec Hybrid in left-hand drive form last year, but living with the car for a week highlights just what a revelation the new powertrain is. Whereas post-facelift E300 BlueTec Hybrids sometimes seem reluctant to switch into electric mode, there鈥檚 no hesitation with the smaller car. Lift off the throttle and the C300 almost immediately switches into 鈥渟ailing鈥?mode, just using the electric motor. And braking regeneration is performed without the car slowing own as soon as you lift off the accelerator. This 鈥済enerator effect鈥?blights some hybrids - Peugeot-Citroen models in particular. Inside, there鈥檚 been a serious raising of the game. The dashboard sweeps across the car - as on the S-Class - though the C-Class retains an analogue instrument cluster, the same as in the new V-Class MPV. A central fixed sat-nav screen is centrally positioned above the air vents, as in the smaller A-Class and B-Class Mercedes models. The quality of the graphics recalls the massive screens of the S-Class.