Upper control panel control module component description - GF54.21-P-6040GZA

MODEL 164.8 with CODE (489) AIRmatic (air suspension with level adjustment without ADS adaptive damping system) with CODE (494) USA version

Location

The upper control panel control unit is located in the center console.

Fig 1: Identifying Upper Control Panel Control Unit

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Task

Scanning the following switches:

ESP OFF switch (N72/1s1)
PTS OFF switch (N72/1s8)
Left front HS [SIH] switch (N72/1s10)
Right front HS [SIH] switch (N72/1s11)
Left front seat ventilation switch (N72/1s13)
Right front seat ventilation switch (N72/1s14)
Level adjustment switch (N72/1s2)
Downhill Speed Regulation switch (N72/1s24)
Offroad program switch (N72/1s25)
Hazard warning system switch (N72/1s5)

Reading in the following function indicator lamps:

Automatic child seat recognition airbag OFF indicator lamp (N72/1e1)
ATA [EDW] function indicator (N72/1e2)

Voltage supply and reading in of data:

of rotary light switch (S1) over an LIN bus
of lower control panel control unit (N72) over an LIN bus

Function

ESP OFF switch

The ESP Off switch can be used to switch the anti-slip control of the "Electronic Stability Program" on and off. The function requirements for this switch is circuit 15 "ON". The function of the ESP systems is indicated in the instrument cluster (A1).

PTS OFF switch

The Parktronic system is activated or deactivated via the PTS OFF switch. If the switch is actuated, the upper control panel control unit sends a signal to the PTS control unit (N62) via CAN-B. The PTS control unit then sends a message requesting actuation of the status LED in the PTS OFF switch back to the upper control panel control unit.

Left front HS [SIH] switch and right front HS [SIH] switch

The heated seats have 3 stages. One-time actuation of the SIH switch activates stage 3 of the heated seats (all 3 red LEDs light up). Further actuations switch to stage 2 (the two lower LEDs go on), to stage 1 (the lowest LED goes on), or the heated seats are switched off (no function indicator). The function requirements for this switch is circuit 15R "ON". Each press of the left front HS [SIH] switch and right front HS [SIH] switch is sent by the upper control panel control unit over the CAN-B.

Left front seat ventilation switch and right front seat ventilation switch (only model 164.8)

When the left front and right front seat ventilation switch is actuated, the upper control panel control unit sends a signal to the HS [SIH], seat ventilation and steering wheel heater control unit (N25/7) via CAN-B.

The switch is used to switch the seat ventilation in the respective seat on and off, and also to control the ventilation output. The level of ventilation output is displayed by indicator lamps in the respective switch.

Level control switch

Function requirements:

Term. 15 "ON"

Function:

Switch actuations enable the driver to choose between a highway level and a raised level. The vehicle is in the highway level state (no function indicator).

If the vehicle is lifted to the raised level, the LED in the switch flashes on and off. When the level is reached the LED remains constantly on. The last stage selected with function indicator is active once the engine is started again.

Downhill Speed Regulation switch

The driver can switch the DSR on and off using the Downhill Speed Regulation switch. A red LED integrated into the switch indicates whether the function is active or not. Downhill Speed Regulation is an aid for driving down hills with an adjustable speed that can be set between 4 and 18 km/h.

Offroad program switch

The offroad program switch is used to adjust the dynamic characteristics of the vehicle in order to optimize traction and forward propulsion in offroad operation

(e.g. by changing the shifting behavior of the automatic transmission).

Hazard warning system switch

Pressing the hazard warning system switch wakes-up the upper control panel control unit from its "Sleep mode" and the hazard warning system function is activated. The message is sent cyclically (every 100 ms) until the function is deactivated by pressing the hazard warning system switch again. The flashing function illumination of the hazard warning system switch is triggered by the CAN message of the rear SAM control unit (N10/8). There is no faster flashing of a defective indicator lamp for the hazard warning flasher system. As soon as the hazard warning flasher function is activated the switch and controls illumination for the hazard warning system switch is switched off. The function illumination of the hazard warning system is not dimmed.

The selected function is confirmed when the indicator lamps (LEDs) light up. The pulse to light up is sent by each respective control unit.

Discrete inputs:

Circuit 30
Circuit 31
CAN-B

Discrete outputs:

Circuit 30
Circuit 31
LIN bus

Voltage limit:

The operating voltage is between 12 and 14 V.