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Wheels, Chassis Alignment Check (Coupe): Overview Smart Fortwo II

Wheel Alignment 2 illustrations ~612 words

General information on vehicle level measurement - AR40.00-P-0202A

MODEL 129, 140, 163, 168, 169, 170, 171, 197, 202, 203, 204, 207, 208, 209, 210, 211, 212, 215, 216, 218, 219, 220, 221, 230, 245, 451

Checking For vehicle level measurement all the vehicle parts must be installed and the vehicle build must be completed ready to drive. 1 Check tire pressure, correct if necessary See tire inflation pressure chart inside the fuel filler flap. 2 Check condition of tires Visual inspection for wear pattern, tread depth and damage. 3 Check condition of rims Visual inspection for damage

All-season tires, disk wheel overview - GF40.10-P-1004MCU

MODEL 451.3 /4

Vehicle/engineDisk wheelET mmTiresAxleSnow chains
451.331 / 132.910 (52 kW)4.5 J x 15 H223,5155/60 R 151
5.5J x 15 H222175/55 R 152
451.331 / 132.910 (52 kW)5 J x 15 H234175/55 R 151
6.5J x 15 H234,5195/50 R 152
451.431 / 132.910 (52 kW)4.5 J x 15 H223,5155/60 R 151
5.5J x 15 H222175/55 R 152
451.431 / 132.910 (52 kW)5 J x 15 H234175/55 R 151
6.5J x 15 H234,5195/50 R 152

MODEL 451.3 /4

Vehicle/engineDisk wheelET mmTiresAxleSnow chains
451.331 / 132.910 (52 kW)4.5 J x 15 H223,5155/60 R 151
5.5J x 15 H222175/55 R 152
451.331 / 132.910 (52 kW)5 J x 15 H234175/55 R 151
6.5J x 15 H234,5195/50 R 152
451.431 / 132.910 (52 kW)4.5 J x 15 H223,5155/60 R 151
5.5J x 15 H222175/55 R 152
451.431 / 132.910 (52 kW)5 J x 15 H234175/55 R 151
6.5J x 15 H234,5195/50 R 152

Contents, function description, tire pressure monitor - GF40.15-P-0999MCU

MODEL 451.3 /4

Tire pressure monitor function GF40.15-P-0001MCU Tire pressure monitor (TPM [RDK]) location of components GF40.15-P-0001-06MCU Tire pressure monitor (TPM [RDK]) block diagram GF40.15-P-0001-07MCU Wiring diagram for tire pressure monitor control unit PE40.15-P-2101MCU Overview of system components for tire pressure monitor (TPM), component description GF40.15-P-9996MCU

Tire pressure monitor control unit, component description - GF40.15-P-5124MCU

MODEL 451.3 /4

Scheme 1

Scheme 1: Tire pressure monitor control unit, component description - GF40.15-P-5124MCU

Location

The TPM [RDK] control unit is located in the footwell on the driver-side.

Task

The TPM [RDK] control unit realizes the following functions

  1. Tire pressure temperature compensation
  2. Warning for pressure loss
  3. Status monitoring

The TPM [RDK] control unit receives data telegrams via two-way radio from the following sensors

  1. Left front TPM [RDK] wheel sensor (A69/1)
  2. Right front TPM [RDK] wheel sensor (A69/2)
  3. Left rear tire pressure monitor sensor (A69/3)
  4. Rear right tire pressure control wheel sensor (A69/4)

The data telegrams contain the pressure, tire pressure temperature, individual serial number and status information (manufacturer, direction of rotation, operating mode etc.).

If a pressure loss is detected, the tire pressure monitor warning lamp (A1e66) in the instrument cluster (A1) is actuated by the TPM [RDK] control unit.

The TPM [RDK] control unit constantly monitors all input signals and output signals for faults. Detected faults that are relevant to function are entered into the fault memory.

Discrete inputs

  1. Circuit 30
  2. Circuit 31

CAN signals

The TPM [RDK] control unit is connected to the Control Area Network (databus/CAN Bus) (CAN) for data exchange.

Wheel sensor, component description - GF40.15-P-5126MCU

MODEL 451.3 /4

Scheme 2

Scheme 2: Wheel sensor, component description - GF40.15-P-5126MCU

Location

The wheel sensors are fastened securely inside the respective rim.

Task

The primary task of the TPM wheel sensors is to measure the pressure/temperature. The measuring range extends from p = 0 and 5.5 bar.

While driving the tire pressure sensors transmit six data messages every t = 60 s. Absolute pressure, tire pressure temperature, wheel identifier and status information (manufacturer, direction of turning, operating mode) are transmitted in these data messages. The TPM [RDK] control unit (N88) receives the data telegrams and assigns (after a learning phase) the wheel identifier to the wheels fitted to the vehicle.

As long as the TPM [RDK] control unit does not recognize the vehicle's own wheel identifier during initial commissioning, no fault message is displayed. After replacing a tire pressure sensor in each case the new tire pressure sensor is taught in and monitored with a new wheel identifier after driving for approx. t = 10 min.

Design

Each TPM wheel sensor is connected to the filling valve via a mounting bolt and forms an assembly unit with it. The assembly unit is attached to the rim flange using a counternut.

The complete assembly unit has to be changed

A wheel sensor consists of the following components

  1. Pressure sensor
  2. Temperature sensor
  3. High-frequency transmitter
  4. Sensor battery for power supply (service life approx. 10 years)

Overview of system components for tire pressure monitor (TPM), component description - GF40.15-P-9996MCU

MODEL 451.3 /4

Instrument cluster, component descriptionA1GF54.30-P-6000MCU
Wheel sensor, component descriptionA69/1, A69/2, A69/3, A69/4GF40.15-P-5126MCU
Outside air temperature sender component descriptionB14GF83.57-P-4000MCC
Component description for the SAM control unitN10/10GF54.21-P-4157MCU
Tire pressure monitor control unit, component descriptionN88GF40.15-P-5124MCU
Cockpit switch group, component descriptionS6/1GF54.25-P-4300MCU
Contents, function description, tire pressure monitorGF40.15-P-0999MCU