Automatic transmission (AT), transmission modes - GF27.10-P-0001-06AHS

Illustration shows instrument cluster (A1), model 221

Fig 1: Identifying Transmission Mode, Multifunction, And Gear Display

Courtesy of MERCEDES-BENZ USA

Gear indicator in instrument cluster in Sport transmission mode "S" and Comfort transmission mode "C"

It shows the driver the shift range currently selected "1, 2, 3, 4, 5, 6" or selector lever position "D, R, N, P".

Gear indicator in instrument cluster in manual transmission mode "M" (except code (494) USA version)

It shows the driver the engaged gear "1, 2, 3, 4, 5, 6, 7" or selector lever position "R, N, P".

Transmission mode display in instrument cluster

It indicates to the driver the program selection Sport "S", Comfort "C" or Manual "M" performed at the transmission modes button (A40/9s8).

The data are sent over the drive train CAN (CAN C) from the fully integrated transmission control unit (VGS) (Y3/8n4) and are forwarded by the CDI control unit (N3/9) or the ME-SFI [ME] control unit (N3/10) over the chassis CAN (CAN E) to the central gateway control unit (N93).

The instrument cluster receives the signal from the central gateway control unit over the central CAN (CAN F).

4 different functions can be selected using the DIRECT SELECT gear selector switch (S16/13) and 3 different transmission modes using the transmission mode button.

Selector lever positions

"P" Park lock and start position

"R" Reverse gear

"N" Neutral and start position (no power transmission, vehicle can move freely)

"D" Drive (all 7 forward gears are available)

Upshifting and downshifting

Upshifting and downshifting is performed using the steering wheel gear shifter PLUS (S111/1) and steering wheel gear shifter MINUS (S110/1) with code (428) Steering wheel shift paddles.

Press +: Upshift by one gear at a time. The shift range is expanded simultaneously in transmission modes "C" and "S". Press and hold: Direct change to gear range "D".

Press -: Downshift by one gear at a time. The shift range is limited simultaneously in transmission modes "C" and "S". Press and hold: The transmission changes into a shift range from which the vehicle can be accelerated or slowed down favorably.

If the shift range is restricted, upshifts occur close to the engine cutoff speed.

View of center console, model 221

Fig 2: Identifying Transmission Mode Button

Courtesy of MERCEDES-BENZ USA

Transmission modes button

The following transmission modes can be selected:

Comfort transmission mode "C"

Starting off always in 2nd gear except in 1st gear range. The gear changes take place at lower engine speed.

Sport transmission mode "S"

Starting off in 1st gear for all driving situations.

Manual transmission mode "M"

Direct gear selection by means of the steering wheel gear shifter MINUS and steering wheel gear shifter PLUS.

When kick-down is actuated the upshifts and downshifts take place as in transmission mode Sport "S".