Patrizia Lipp - the voice of the ur-quattro
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Patrizia Lipp - the voice of the ur-quattro
All WR-engined Audi ur-quattros with green digital dashboards (late 1983 to 1987 model years) were equipped with an autocheck unit including an electronic voice synthesiser. This unit was developed so that some twenty sensors could be monitored without cluttering the dashboard with a plethora of warning lights. It also allowed warnings to be prioritized - brake system defects are more important than washer bottle fluid levels.
On many cars, the audible warning system is not working or is working incorrectly. This may be the result of incompetent radio installers or deliberate crippling so that a car with major faults can be sold. Some systems have been disabled because a mechanic was incapable of diagnosing and repairing the identified faults. In many cases the unit has even been physically removed from the vehicle. On many cars the unit has its own direct-to-battery power supply - one red and one brown or black wire in a loose sheath running under the carpet between the front seats and surfacing under the rear seat. The wires go to small male spades on the battery terminals.
If the unit is incompetently disabled, several potentially serious brake system problems (brake fluid level, hydraulic reservoir pressure, hydraulic supply pressure) will not be indicated to the driver via a warning light.
The audible warning unit is a critical safety feature and must be in working order.
NEVER permit the voice synthesiser to be disabled because the warning messages cannot be dealt with - find a more competent mechanic. The fact that some cars use audible warnings and some do not - even some ur-quattros - does not mean that the feature can safely be disabled. It is NOT a fashion accessory.
One major source of problems is a pair of black or black/purple three-pin connectors in the wiring loom a few inches from the back of the autocheck unit, which is physically situated just behind and below the radio. One of the connectors has one wire looped to all pins. These connectors should NOT be mated when the autocheck unit is present, otherwise spurious errors may be incorrectly indicated for the braking system. It's possible to check whether these connectors are mated without dismantling the centre console by pulling off the handbrake and brake fluid level switch leads and checking for continuity between the non-brown wires on each. Note that some cars have two pairs of black/purple connectors - only the one with the looped wire should be disconnected.
The system uses the radio loudspeakers. On 1983/4 cars (autocheck unit 857 907 399A) the left and right outputs from the radio are looped through the unit to the fader. If the autocheck unit wants to issue a warning, it breaks the loop and outputs its audible warning on both channels - to all loudspeakers via the fader. On 1985/6/7 cars (autocheck unit 857 907 399E) the fader is in the stock radio and only one loudspeaker (usually the front left) is taken through the autocheck unit. A signal is output on Pin 16 to the radio NF terminal - this mutes the radio and silences the other three loudspeakers while the audible warning is issued on the one connected through the autocheck unit.
Care should be taken to retain the audible warning functions if the stock radio is replaced with any other system. Special care should be taken if separate amplification is used, since the volume of audible warnings is not adjustable. In 1983/4 cars, the amplifier outputs can be brought back through the unit. In 1985/6/7 cars, it may be appropriate to fit an additional loudspeaker just for the audible warnings, using the radio's NF input to mute all other loudspeakers.
Note that the autocheck connector performs a useful function even in vehicles that do not have an autocheck unit - if the main connector is cut from the loom, the warning signal passing through Pin 29 on a blue/green wire (all versions) from T3 to the dashboard light is lost. If this connector is missing, it can be replaced by an autocheck connector from a standard (non-turbo) Audi 100 - which harness colour to attach to which pin can be found in the pages below.
The two versions of the autocheck unit (suffix A and suffix E) are significantly different in many ways (e.g., radio mute signal, oil pressure warning) and are not interchangeable.
The schematics and notes vary by model year:
For the technically inclined, the Suffix A verion is based on a National Semiconductor 54104 Digitalker processor, as first shown on Stand 7602 at the Hannover Fair in 1980. When you first hear a little box say: "Ich hab' die Nase voll, ich mach' nicht mehr mit" it's quite a novelty. When you provide a button for the public to trigger this, and they queue up to do so, it can prove tedious after a few hours. The announcement that the exhibit was being withdrawn during exhibitor hour before the fair opened next morning was greeted with a stunning response from all the other exhibitors - rapturous applause, whistling and foot-stamping. Especially from the manager of Stand 7602, upstairs at the time preparing for another day gargling with neat gin.
The Suffix E version was a complete redesign. Both versions use relays to switch the loudspeaker outputs, and these occasionally need cleaning - the compound relay fitted to the Suffix A version has a plastic cover that must be prised off - the three smaller relays used in the Suffix E can be cleaned directly.
No, not drinking it. Gargling with it to kill throat germs.