51.md

0x51 Check Control Status

CCM 0x30 → Broadcast 0xbf

Only applies to low cluster (KOMBI)!

The Check Control Module (CCM) reports certain sensors to cluster, such as Washer Fluid Low, Brake Fluid Low etc. Later models, like the E46 have all these sensors connected directly to the IKE.

Note: The CCM was originally a discrete module in early E38s, but it was soon integrated into the light module which is found on later E38s, E39s, E46 etc.

Examples

30 04 BF 51 01 DB
30 04 BF 51 02 D8

Related Commands

• 0x1a Check Control Message
• 0x1b Check Control Priority
• 0x50 Check Control Status Request
• 0x52 Check Control Message Relay

Parameters

Fixed length. 1-byte bitfield for LCM_III (and I'd guess earlier variants).

BRAKE_FLUID_LOW     = 0b0000_0001
FASTEN_SEATBELT     = 0b0000_0010
KEY_IN_IGNITION     = 0b0000_0100
UNKNOWN             = 0b0000_1000

WASHER_FLUID_LOW    = 0b0001_0000
UNKNOWN             = 0b0010_0000
OIL_LEVEL           = 0b0100_0000
UNKNOWN             = 0b1000_0000

Use Cases

Indicator and warning lamps

Many of the systems of your BMW monitor themselves automatically, both during engine starts and while you are driving. Indicator and warning lamps that are identified by "●" are tested for proper functioning whenever the ignition key is turned. They each light up once for different periods of time.

Brake Fluid

30 04 BF 51 01 DB   # Turn on Brake Fluid low indicator (Red exclamation sign)

Fasten Seatbelt

30 04 BF 51 02 D8   # Turn on Fasten Seatbelt indicator

Engine Oil Level

While using the same icon, the oil level indicator is yellow, while the oil pressure indicator is red.

Yellow: Stop immediately

Yellow: Check as soon as possible

30 04 BF 51 40 FA   # Turn on Engine Oil Level indicator

Check Control (Low/KOMBI)

On vehicles with the basic system, information is indicated not in the form of text messages but rather by warning lamps and symbols in the LC display field for check control messages in the instrument cluster.

The following warning lamps/symbols are dependent on this command.

2. Add washer fluid (goes out after approx. 1 minute)

The following warning signal sounds are also dependent on this command.

When you open the door after stopping, a warning signal sounds without a visual indicator for:

• KEY IN IGNITION LOCK

Washer Fluid

The following alerts or status messages are displayed symbolically from ignition key position 2 and up until the defects are corrected:

2. Add washer fluid (goes out after approx. 1 minute)

30 04 BF 51 10 CA   # Turn on Washer Fluid Low indicator

Key In Ignition

When you open the door after stopping, a warning signal sounds without a visual indicator for:

• KEY IN IGNITION LOCK.

30 04 BF 51 04 DE   # Cluster will play chime when door opens