Fuel Gauge - Fluctuating Reading While Driving
Article No. 85-22-3FUEL GAUGE
- FLUCTUATING
READING DURING DRIVE MANEUVERS - SEDANS BUILT BEFORE MAY 2, 1985, AT CHICAGO AND BEFORE MAY 3, 1985, AT ATLANTA ASSEMBLY PLANTS
FORD 1984-85 LTD
LINCOLN-MERCURY 1984-85 MARQUIS
A fuel level gauge showing a fluctuating fuel level reading is caused by fuel slosh in the fuel tank reservoir during cornering, braking and accelerating. These maneuvers cause the fuel sender float to rise and fall, creating the fluctuation seen on the fuel gauge.
Figure 6 - LTD/MARQUIS FUEL GAUGE DAMPING CIRCUIT PART NUMBER E5PZ-10E849-A:
Figure 7 - LTD/MARQUIS FUEL GAUGE DAMPING CIRCUIT INSTALLATION/INSTRUMENT CLUSTER TERMINALS:
To correct this condition, an electronic dampening circuit (part number E5PZ-10E849-A) has been developed to filter out the fluctuating fuel signals from the fuel sender. This circuit is mounted to the back of the instrument cluster and wired to the fuel gauge circuit. The fuel gauge dampening circuit installation instructions follow. Refer to Figures 6 and 7.
1. Remove cluster as described in 1985 Car Shop Manual, Section 33-01.
2. Place cluster face down with speedometer head to left.
3. Remove protective adhesive cover from velcro strip on back of the circuit board and stick the circuit board to upper left side of cluster (between illumination bulb and step) with wires directed toward the speedometer.
4. Unsnap printed circuit (Instrument Voltage Regulator) (I.V.R.). Attach TAN/ORANGE wire (with snap ends) to output side of I.V.R.
NOTE: The ignition post has an embossed identification.
5. Attach the YELLOW wire (with snap ends) to ignition post of instrument Voltage Regulator (I.V.R.). Snap printed circuit back onto new snaps of tan/orange and yellow wires.
6. Route BLACK/ORANGE wire between speedometer and I.V.R., under cluster plug-in socket to the gauge stud (stud closest to center). Attach the solderless terminal with the lock washer and (No. 10-32) nut provided.
7. Remove the I.V.R. mounting screw and insert the BLACK wire eyelet (solderless terminal) between screw head and I.V.R. mounting bracket.
8. Disconnect the GREEN and RED wires from the amplifier circuit assembly at the quick disconnects.
9. Rework the 14401 wiring harness assembly (at the instrument cluster plug) as follows:
9A. Cut circuit No. 29 (Pin No. 6, Y/W) at the base of the Integrated Circuit (I.C.) plug and splice to the GREEN wire which was disconnected from the amplifier circuit with the solderless connector provided.
9B. Cut circuit No. 279 (Pin No. 10, BK/LG H - may be WHITE with PINK stripe. Ensure that connection is made to Pin No. 10 marked on connector.) at the base of the I.C. plug and splice to the RED wire which was disconnected from the amplifier circuit with the solderless connector provided.
10. Reinstall the instrument cluster per Shop Manual instructions, including attachment of the GREEN and RED wire quick connects, watching that the BLACK/ORANGE wire does not interfere with insertion of the instrument cluster electrical plug, 11. If the car is equipped with the Low Fuel Warning Light option, the low fuel warning module assembly (basic part number 9H326) must be changed to maintain compatibility with the revised gauge system circuit. Replace the Orange module with a Black module (part number D1VY-9F326-A).
PART NUMBER PART NAME CLASS
E5PZ-10E849-A Fuel Gauge - Amplifier A
Assembly
OTHER APPLICABLE ARTICLES: Supersedes 84-19-10
WARRANTY STATUS: Reimbursable within the provisions of the Warranty and Policy Manual.
OPERATION: SP10849A85
TIME: 0.8 Hr. DLR. CODING: Basic Part No. 10E849 - Code: 09