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Trip Computer - Miles to Empty Reads Low While Driving


91audi06

Group: 91

Number: 91-11


Date: 10/31/91


Subject:
Trip Computer MPG/Miles To Empty Reads Low While Driving


Model(s):
100,80/90 with CIS-E III M.Y. 1989-1991


Condition:

Excessive voltage output signal being produced at pin ten of the fuel injection control unit.


Service:





Test drive vehicle if trip computer MPG or miles to go (Mi) read low or stays on a fixed value i.e. 5 MPG, then do the following:

Perform board computer code check.

Refer to Microfiche repair manual - Group 91.


Note:

It is not necessary to remove instrument panel to retrieve code.





If code cannot be retrieved, connect the VAG 1598-3 to the fuel injection control unit. With the VAG 1598 measure voltage at pin ten with the engine at idle. Voltage should vary between 0.3 and 0.8 volts. (Corresponding to engine RPM).

If voltage is higher than 1.0 volts and fluctuating replace fuel injection control unit.


Important:

The miles to empty may not register correctly until reset after driving.