Mountaineer AWD V6-4.0L VIN K Flex Fuel (2003)
Technical Service Bulletin # 06-2-12
Date: 060206
Instruments - Fuel Gauge Drops to Empty/MIL ON/DTC's
TSB 06-2-12
02/06/06
MIL ON WITH PCM DTC P0463 AND/OR IC DTC
B1201 - FUEL GAUGE DROPS TO EMPTY OR SLOW
TO UPDATE AFTER REFUELING
FORD:
2002-2006 Explorer
LINCOLN:
2003-2005 Aviator
MERCURY:
2002-2006 Mountaineer
This article supersedes TSB 05-21-3 to update the Service Procedure.
ISSUE
Some 2002-2006 Explorer/Mountaineer and 2003-2005 Aviator vehicles may exhibit a customer complaint of the fuel gauge being slow to read full after
refueling, the malfunction indicator lamp (MIL) on with diagnostic trouble code (DTC) P0463, instrument cluster DTC B1201, and/or the fuel gauge
dropping to empty. This may be due to the fuel level sender assembly sending incorrect data to the instrument cluster and/or powertrain control module
(PCM).
ACTION
Refer to the following General Information for a description of two (2) modes of fuel gauge operation prior to following the TSB Service Procedure.
This brief explanation of current fuel gauge strategy will help ensure the correct diagnosis is made. The fuel gauge on these vehicles has several distinct
modes of operation. The difference in the various modes is the speed at which the fuel gauge pointer moves in relationship to fuel level input from the
fuel level sender. After reviewing the General Information, refer to the TSB Service Procedure.
GENERAL INFORMATION
Fuel gauge strategy provides several modes of operation. One being referred to as Fast Acquire Mode and another as Slosh Mode. The time for the fuel
gauge pointer to move from "E" to "F" can be 2 seconds, 17 minutes or 55 minutes depending on build date and which mode the fuel gauge is in.
Fast Acquire Mode:
The 2-second "E" to "F" mode is referred to as Fast Acquire Mode. Fast Acquire Mode strategy requires two (2) conditions to be met before the fuel
gauge indications can be updated. First, at least four (4) gallons of fuel must be added to the fuel tank. Second, the Instrument Cluster must acquire a
valid Key-ON fuel sender reading within 1 second of the key being put in the Run position. The Key-ON sample reading is considered valid if the fuel
sender reading is between 10 and 160 ohms. If both of these conditions are not met, the fuel gauge stays in Slosh mode. If the Cluster does not go into
Fast Acquire Mode after a refueling event, the system will stay in Slosh Mode. This will result in a slow to Read Full event.
Slosh Mode:
The 55-minute "E" to "F" mode is referred to as Slosh Mode. In Slosh Mode, this is 55 accumulated minutes of the key in the Run position. Unless the
conditions are met to put the fuel gauge into one of the other operating modes, the default is Slosh Mode. Example: If a customer operates their vehicle
11 minutes per day, it will take 5 days to accumulate 55 minutes of run time. This means it will take 5 days for the fuel gauge to go from "E" to "F".
NOTE
SLOSH MOD[ STRATEGY WAS REDUCED FROM 55 MINUTES TO 17 MINUTES FOR VEHICLES BUILT AFTER 12/22/2004.
NOTE
IT IS IMPORTANT TO THOROUGHLY UNDERSTAND THE CUSTOMER CONDITION BEING REPORTED.
It is important to determine if the customer has a fuel gauge that slowly gets to full or has a fuel gauge that never gets to "F" (stuck) when the fuel tank is
filled. If the fuel gauge slowly goes from "E" to "F" (in 55 minutes of key in the Run position or less), the problem is most likely not in the cluster. It is
absolutely imperative that the appropriate pinpoint test(s), located in the Workshop Manual or this TSB, be completed for this customer complaint to
determine root cause of the condition. Root causes may include but are not limited to: the Fuel Sender, Fuel Tank, Wiring, or Instrument Cluster
WARRANTY STATUS: Eligible Under Provisions Of New Vehicle Limited Warranty Coverage
