BMW TPM light or warning message may come ON when there is air loss in one or more tires.

As BMW Tire Pressure Monitor System detects a 20% loss in tire pressure it triggers a TPM warning to alert the driver.

BMW TPM TPMS Warning Light

If tire pressure is correct, you may be getting a TPM malfunction or inactive errors because:

  • TPMS sensor is defective
  • RDC module is faulty
  • External interference

What to do?

BMW tpm pressure

If you are getting tire pressure warning message, the first thing you need to do is to check tire pressure with a tire pressure gauge.

bmw recommened tire pressure

Inflate all the tires as recommended on the tire pressure label that can be found on the driver's door frame or behind the gas cap access panel. Typical BMW tire pressure is 32-36 PSI.

How does BMW TPM work?

TPM has pressure sensors in each wheel and a control unit ( also known as RDC, TPM, TPMS receiver) is installed in the vehicle.

This system monitors tire pressure and warns the driver if pressure is too low. Proper tire pressure (typically 36 psi) will ensure the best performance, fuel economy and extend tire life.

Common Problems

Defective RDC Transmitter

Older BMW models, with generation 1 or generation 2 TPM systems, have a sensor within the tire and a transmitter in each wheel well, hidden behind the underliner.

Transmitters pick up the signal from sensors and send them to the central control unit, which has an antenna. In most cases, a transmitter can go bad, causing a break of communication.

It is also possible for a reception antenna in the control unit to fail.

Water Damage

Newer BMW models, equipped with generation 3 or later TPM systems, use a more simplified system. With no wheel transmitters, wheel sensors combined with a single control unit that has an integrated antenna are the only components.

Depending on the model year, the control unit is mounted on the chassis, which makes it exposed to the elements. As a result, moisture enters the casing, causing corrosion on sensitive electronic components.

Although sealed, the control unit can be opened with a bit of effort. Clean any traces of corrosion, which are green in most cases.

BMW tire pressure module (A85a) may be installed under the spare tire or under the dashboard on the driver's side.

A common problem with BMW tire pressure system is when the RDC module is installed under the spare tire in the trunk floor.

Water can build up under the spare tire which in turn damages the module or causes corrosion to the contacts.

TPM Fuse

blown tpm fuse

Lastly, check the TPM fuse, as it can burn if the control unit shorts out.

In most models, this fuse is located in the junction box behind the glove compartment.

TPM Sensor Battery

BMW TPM sensor

Within each tire, there is a sensor that gives information about the air pressure.

They have a lithium-ion battery, which drains out with time. In most cases, OEM batteries can last up to 10 years.

Another possibility is mechanical damage, which can happen during tire fitment.

Most tire shops have wireless readers that can verify if the sensor is emitting the signal.

Reset BMW TPM warning

The next step is to reset the TPM warning.

  1. Inflate the tires to the recommended tire pressure. Typically 36 PSI.
  2. Press iDrive knob to select vehicle settings.
  3. Scroll down to Vehicle Tires using the iDrive knob.
  4. Rotate the iDrive knob to select the TPM menu.
  5. Select Reset then press iDrive knob.
  6. Select YES. Status should change to Resetting TPM.
  7. After a short drive Status should change to TPM Active.

Because of various transportation acts, a TPM system is mandatory for all new cars sold in the United States after September 2007. So, all BMW cars from 2008 have a TPM system installed from the factory, regardless of the model and equipment level.

Possible Error Messages

  • Tire Pressure Monitor TPM for the detection of flat tires is currently unavailable. Please contact the nearest BMW
  • TPM Status: TPM Malfunction
  • Tire Pressure Monitor (TPM) malfunction:
    • System unable to detect tire pressure loss
    • Check tire pressure manually
    • Continued driving is possible
    • Consult service center
  • Tire Pressure Monitormalfunction: Drive moderately. The system is unable to detect tire pressure loss. Consult service center.
  • TPM Inactive warning light on the dashboard.
  • Statut Vehicule: Controle de pression des pneus (RDC) actif.
  • Tire pressure monitor reset: System inactive and unable to detect pressure loss for up to 12 minutes. Reset only occurs while driving.
  • Low tire pressure. Stop carefully. For Run Flat tires with the "RSC" symbol, you can continue driving with max. 50 mph (80 km/h).

Diagnose BMW TPM System

To diagnose BMW tire system malfunction you will need an OBD-II scanner that can read and clear BMW specific fault codes.

Generic OBD-II scanners won't be able to read BMW TPM fault codes such as:

  • 604E RDC System Malfunction
  • 6050 RDC Transmitter, front right
  • 6055 Wheel electronics, front right

TPMS and Run-Flat Tires

In addition, as most new BMW cars have run-flat tires, an inoperable TPM system can be a safety issue.

Depending on the type, cars with run-flat tires can drive up to 55 mph and up to 200 miles in distance with underinflated tires.

While conventional tires have soft sidewalls that deflect when unpressurized, a run-flat tire has a strong sidewall structure.

However, as these tires can support the weight of the car and maintain their shape with no air inside, a driver might not notice a punctured tire.

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Visitor
Member since 2020-07

Hi there, I have a BMW 420 convertible (65 plate). I recently had the common problem of water sloshing around in the panels due to blocked drains. However, the car has also come up with RDC failure which is what prompted me to research the water sloshing sound. BMW have cleared and modified the drains but are saying that the RDC failure has nothing to do with the water ingress. Where is the RDC module and antennae located on these models and is it possible that water ingress in the boot, particularly in the rear right where there are a number of electrics can cause the problem?

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