GF54.30-D-2014H Indicator Lamp Test and Engine Running Detection, Function

GF54.30-D-2014H Indicator Lamp Test And Engine Running Detection, Function








Shown with engine 272 and with code (JK3) High-end instrument cluster standard with speedometer in km
A1 Instrument cluster
B70 Crankshaft sensor
G2/7 Alternator
N3/23 ME control unit
N10 SAM control unit

Indicator lamp test
An indicator lamp test is performed via the instrument cluster at "circuit 15 ON". All available indicator and warning lamps are actuated, except:
- Left turn signal indicator lamp (A1e10)
- Right turn signal indicator lamp (A1e20)
- High beam indicator lamp (A1e3)
- Seat belt reminder light (A1e6)
- Preglow indicator lamp (A1e13), with engine 642 or with engine 646

The indicator lamp test occurs only for as long as the Controller Area Network (data bus/CAN bus) (CAN) message "circuit 61 < 9 V" is present at the instrument cluster.

Engine running recognition "circuit 61e"
The instrument cluster links the CAN messages "Circuit 61" and "Engine speed" to a CAN message at "Circuit 61e" (engine operation detection). This CAN message can have either a "HIGH" or "LOW" status.
It is "LOW" when the status is "circuit 61 < 9 V" and the engine speed is below 200 rpm for longer than 0.5 s.
If the engine speed is > 480 rpm for longer than 0.5 s, the CAN message "HIGH" is sent. The signal "Circuit 61e" is placed by the instrument cluster on the Controller Area Network bus class C (engine compartment) (CAN-C) and as a result is available to the control units which need this CAN message.

Networking
The circuit 61 signal, from the alternator (alternator check), is read in by the SAM control unit. The SAM control unit then places the message "circuit 61 HIGH" (alternator functioning) or "circuit 61 LOW" (alternator not functioning) on the Controller Area Network bus class B (interior) (CAN-B).

Engine speed
Determining the engine speed:
- The rotational speed is detected by the crankshaft sensor.
- The signals from the crankshaft sensor are read in by the CDI control unit (N3/20), the CDI control unit (N3/21) or the ME-SFI [ME] control unit (N3/23) and placed on CAN-C.
- The instrument cluster receives these signals and processes them.

The same CAN messages are used for the charge indicator warning message on the display (A1p1) or for actuating the alternator warning lamp (A1e7).