9000 L4-2290cc 2.3L DOHC Turbo EFI (1992)
Driver/Vehicle Information Display: All Technical Service Bulletins
Instruments - (EDU) Low Fuel Consumption Reading
CATEGORY
Electrical
SECTION
3
PAGE
44
ISSUE
06/93-0349
CODE
381
Subject:
Excessively Low EDU Average Fuel
Consumption Reading
Application:
1990- 9000 Models
A service procedure has been developed to remedy complaints of low fuel consumption readings. For example, a customer may complain that the
average fuel consumption readout on the EDU is 29 MPG, while their actual (calculated) consumption is 24 MPG.
When the ignition is switched off, voltage remains present on the speed input (pin 9) of the EDU for an additional five minutes.
On some cars with numerous systems connected to the speedometer's speed output, this voltage may be above the EDU's threshold level and cause it to
continue counting the distance covered (mileage) during the five minutes it is active after the car is shut off.
This affects the EDU's calculation of average fuel consumption, causing it to show a varying, excessively low figure while "distance to empty" is
correspondingly too high.
The fault is also noticeable in that the average fuel consumption figure will change when the car has been parked overnight. The fault can be remedied by
installing a diode between the speed signal and switched power.
Cars Affected:
1990- Saab 9000 Models up to:
P1011827 inclusive, manual gearbox
P1011697 inclusive, automatic transmission
Parts:
Service kit 44 39 295, which contains the following items:
^
Diode 1N 4140 with soldered leads, one yellow and one green.
^
Cable terminals 91 20 783
^
1 Cable tie 79 71 864
Action:
