Operation and Function

NOTE: If the wiring loom is defective, it must not be repaired. Defective dash panel insert wiring looms must be replaced.

The following tools are required for troubleshooting:

^ Multimeter Fluke 83 (US 1119)
^ Connector test kit VW 1594
^ Test box VAG1598 with adapter harness VAG 1598/8
^ Instrument tester VW 1301
^ Digital potentiometer VAG 1630
^ Valid wiring diagram

Operation and Function
The Multi-function indicator is an integral part of the instrument cluster and consists of an electronic processor unit and a digital display unit.
Electrical signals from external components (sensors and control modules) are fed into the electronic unit, processed and stored. The results can be shown as figures in the display.

The multi-function indicator mode select switch E86 and the multi-function indicator memory switch E109 are located in the wiper switch lever.
The following signals are processed by the multi-function indicator:

- Pulse from speedometer vehicle speed sensor (VSS) G22
- Resistance change from engine oil temperature sensor G8
- Resistance change from outside air temperature sensor G17
- Fuel consumption signal from engine control module
- Pulse from terminal TD/terminal 1

When the ignition is off, the MFA display shows time. When ignition is switched on, the time remains in the display until the multi-function indicator mode switch E86 is pressed. When the multi-function indicator mode select switch E86 is pressed briefly and repeatedly, different functions appear one after the other.

Sequence of functions:

- Time (in hrs and minutes)
- Driving time (max. 100 hrs)
- Average fuel consumption (liters/100km or miles/gallon)
- Distance driven (max. 10,000km or 10,000 miles)
- Average speed (in km/h or mph)
- Engine oil temperature (in degrees Celsius or Fahrenheit)
At temperatures below 122°F (50°C) dashes appear.
- Outside (ambient) temperature (in degrees Celsius or Fahrenheit)

When ignition is on, the sensor values for driving time, distance and fuel consumption are recorded continuously and stored. The calculation of the average speed and the average fuel consumption only takes place when the function is called up.

Driving Data Memory
The multi-function indicator contains two selectable memories. The data in these memories can be displayed using the multi-function indicator mode select switch E86.

- Memory 1: Single trip memory
- Memory 2: Total trip memory

The two memories collect all driving data as long as the ignition is on. Both memories can be cancelled manually. If the capacity in one memory is exceeded, all data in this memory will be cancelled. Memory 1 (single trip memory) will automatically be cancelled when ignition is switched on if the ignition has been off continuously for longer than 120 min.

Multi-Function Indicator Mode Select Switch and Memory Switch
In position 1 of multi-function indicator mode select switch E86 the contents of the single trip memory can be displayed. With ignition on, and until the ignition is switched off, the following data is collected:

- Driving time
- Distance driven
- Fuel consumed

From This data the average speed and the average fuel consumption are calculated and stored. It the trip is continued within two hrs of switching off the ignition, the new values are included in the calculation.

In position 2 of multi-function indicator mode select switch E86 the contents of the total trip memory can be displayed. The following data from any number of single trips is collected:

- Driving time (up to 100 hrs)
- Distance driven (up to 10,000 km/miles)
- Fuel consumed (1,000 liters/gallons)

From this data the average speed and consumption for all single trips are calculated and stored. If one of the given maximum memory capacities is exceeded, the memory is cancelled and the calculations start over once again. Unlike the single trip memory, the total trip memory is not cancelled after switching the ignition off for two hours.

Cancelling the Memories
Both memories can be cancelled separately with the ignition on. To cancel memories, slide multi-function indicator memory switch E109 fully left (for memory 1) or fully right (for memory 2) into position 0 and hold longer than 1 sec. If battery is disconnected, then both memories are cancelled automatically.

Setting the Time
To set the time there are two buttons on the left below the engine coolant temperature (ECM) gauge G3. The upper button (h) is for the hours and the lower one (min) for the minutes. Pressing the appropriate button briefly will advance the time one hour or minutes. With button depressed, hours or minutes will advance continuously.

Troubleshooting - Checking Multi-function Indicator:

Multi-function Indicator (MFA) Check Mode Test
If the display values for the momentary fuel consumption, oil temperature or outside air (ambient) temperature are inaccurate, perform check mode test before attempting repairs:

- Switch ignition on
- Press multi-function indicator mode select switch E86
- Switch ignition off, then back on and hold multi-function indicator mode select switch E86

The value for momentary fuel consumption appears in the display. Press and release mode select switch E86 to call up oil temperature, then outside air (ambient) temperature. The selected function appears in the display. The data in the display is aligned on the right hand side.