F 250 4WD LD Pickup V8-5.4L SOHC VIN L (1997)
Four Wheel Drive Selector Switch: All Technical Service Bulletins
Transfer Case - Multiple Electrical Malfunctions
Article No.
01-16-6
08/20/01
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LAMP - 4X4 "LOW RANGE" LIGHT DIMLY LIT
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SWITCHES - TRANSFER CASE MODE SWITCH - 4X4 HI/LOW SWITCH SHORTED OUT
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WINDSHIELD WIPERS - INTERMITTENT WIPERS ERRATIC OR INOPERABLE
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TRANSFER CASE - WATER PRESENT IN TRANSFER CASE
FORD:
1997 EXPEDITION, F-150, F-250 LD
This article is being republished in its entirety to update the labor time.
ISSUE
Water may be present in the transfer case on some vehicles. This may cause:
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Transfer Case Mode Switch to become inoperative
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The 4X4 "Low Range" light to appear dimly lit
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The intermittent wipers to become erratic or inoperative
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Vehicle Speed Sensor (VSS) Diagnostic Trouble Codes (DTCs) P0500, P0503, P1500, and P1501 to be set.
This may be caused by water splashing into the transfer case through the vent tube assembly, possibly causing the transfer case mode switch to short out,
and/or the VSS gear to swell and set the VSS DTCs listed above. Shorting out the transfer case mode switch may cause the intermittent wiper mode to
function erratically, as well as possibly causing the 4X4 light to work incorrectly.
ACTION
Inspect, diagnose, and/or replace the necessary components. Refer to the following Service Procedure for details.
SERVICE PROCEDURE
Procedure for VSS Gear:
1.
Inspect VSS gear in the transfer case for looseness.
2.
Replace Gear (C80Z-17285-B) as necessary. Refer to Section 308-07B of the 1997 F-150/250 Workshop Manual for removal and installation
procedures.
Procedure for Transfer Case Mode Switch:
1.
Check resistance of the Transfer Case Mode Switch.
2.
The resistance of the switch should be at least 100,000 ohms. If it is less, replace the switch (3-Position Switch, E7TZ-7E440-A, manual shift
only). Refer to Section 308-07B of the 1997 F-150/250 Workshop Manual for removal and installation procedures.
Procedure for Transfer Case Vent Replacement:
1.
Remove old vent hose from fitting on front of transfer case.