Electronic Throttle Control (EML)

Electronic Throttle Control (EML):

Notes on the BMW DIAGNOSTIC SYSTEM:

Defect Code Memory:

The component functions and signals listed below are processed or controlled by the EML control unit, but not stored as a defect code in the event of defect:

- LL-signal (sends the "idle" information to the DME)
- VL-signal (sends the "full load" information to the DME)
- Air conditioning switch
- A/C compressor clutch (lock sensor)
- Range selector switch ("P"or "N" position in automatic transmission)
- Brake light switch
- External safety path

The external safety path cannot be read out in the status lists of the BMW DIAGNOSTIC SYSTEM.

Defect Code Priority:

The EML control unit stores a maximum of 5 defect codes. When the defect code memory is full, a new defect code with higher priority displaces a lower priority defect code already stored.

Status Monitoring:

Since all inputs and outputs and their plausibilities are not covered by the defect code memory of the EML control unit, the status monitoring function must be used to facilitate troubleshooting.

The nominal values and actual values indicated in the status lists need not necessarily agree exactly. The EML control unit stores a defect code if the deviation between the nominal value and the actual value is outside the permissible range.

For the permissible ranges, refer to the functional description or the troubleshooting description in the BMW DIAGNOSTIC SYSTEM. If the permissible range has been exceeded and the EML control unit has detected this as a defect, the component and its line connection can be checked without complex measurements with the aid of the actual value display.

Troubleshooting:

Notes: Troubleshooting takes place in accordance with the data provided in the BMW DIAGNOSTIC SYSTEM.
Description of BMW DIAGNOSTIC SYSTEM

Important!

- Relevant safety codes and accident prevention regulations must be observed when carrying out all tests and work on the engine electronic system. Do not touch an EML throttle valve when it is in operation.

Wherever possible, the battery and the instrument cluster should not be disconnected otherwise all defect codes and teach-in values stored in the EML control unit will be deleted.

Disconnect control unit from the wire harness only when the ignition is switched off.

Caution!

The stage outputs of the EML control unit for the throttle (DK) actuators are not short-circuit-proof. In the same way, the 5 V component supply voltage coming from the EML control unit is not absolutely short-circuit-proof.

Structure of the Defect Code Page. on the Display Screen:

- Defect location: The defect can be in the vicinity of the component, the associated wires or in the control unit. The number before the defect code indicates the priority of the defect code.

- Type of defect: Range transgression or illogical (wrong sequence) functions are indicated.

- Detected at: Additional defect information on the operating statuses during defect detection (compare values with substitute values). This information indicates relationships to other defects.

EML Warning Lamp:

After switching on the ignition, the EML control unit performs a safety check and causes the EML warning lamp to light for approx. 2 seconds. The engine output (throttle setting) is reduced if the warning lamp is defective. The warning lamp lights permanently if a defect with high priority (defect code 8 to 22) occurs.