MPG dash display stopped working

[RoadKill]

whats used to work out the MPG mines stopped working and is stuck on 5MPG

[UrS4boy]

whats used to work out the MPG mines stopped working and is stuck on 5MPG

I will seek out your S2 answer in my next post. In the meantime, for an UrS4/S6 with the trip computer, the wire you seek is a Blue/Black (0.5) wire from the ECU pin T55/31 (T55/31- Fuel consumption signal for trip computer - BL/BK Enters the J128 Board Computer at Pin T10a/5 - Note: only used in N.America on 92 spec UrS4s). This wire is connected to the dash in position 5/6 of the red T6c connection in Connector Stn 2 (passenger side kick panel), as noted below from:

http://12v.org/urs/AANEngineHarnessPassengerSideV2.pdf

T6c, Red 6 pin connector. (Connector Stn 2, Right hand front kick panel, behind the orange and
grey connectors - at least for LHD UrS4 cars)) (Base photo courtesy of typ44quattro)

1/6 Brown/Red (0.5) Vehicle Speed Sensor (G22) ( More G22 Vehicle Speed Sensor info)

3/6 Black/Blue (1.5) from Fuse S14 in dash fuse panel, on to many devices, including back-up lights
and ECU pin T55/22, via a Data Link Connector – as W/BL wire - linked to Check engine light (Malfunction
indicator lamp) - also used in the blink code check.)

4/6 Blue/Red (1.0) After staring at the Bentley for an hour and then looking at my spare (but damaged
– wires cut at the connector) harness AND then going out to my 93 UrS4, I (UrS4boy) finally figured it
out: There is a 1.0 Blue/Red wire coming into 4/6 of T6c from the F4 Manual Transmission Backup Light
switch AND there are two Blue/Red wires going out: One 0.5 going to T26/3 of the mirror control module
(presumably for the mirror dip function), and one 1.5 going to the back up lights

5/6 Blue/Black (0.5) ECU pin 31 (T55/31- Fuel consumption signal for trip computer - BL/BK Enters the
J128 Board Computer at Pin T10a/5 - Note: only used in N.America on 92 spec UrS4s)

6/6 Grey/Red (0.5) Hydraulic Pressure Control Switch (F79) (relates to the brake system and connects
to the Autocheck at T14/10) (The grey/red and a ground are connected underneath the Master cylinder
via two separate spade connectors (no plastic housing) (Base photos courtesy of typ44quattro)

[UrS4boy]

Looks like it is still Pin T55/31 on an ABY but the colours are different. The intermediate connector between the J220 ECU and the J128 trip computer is T5, position 3. The T5 is black and is located in the auxiliary relay carrier, presumably as shown in the photo below, under the wiring diagram.

Source: http://www.s2central.net/S2_Schematics/B/B73.PDF