Transfer Case - Multiple Electrical Malfunctions

Article No.
01-16-6

08/20/01

^ LAMP - 4X4 "LOW RANGE" LIGHT DIMLY LIT

^ SWITCHES - TRANSFER CASE MODE SWITCH - 4X4 HI/LOW SWITCH SHORTED OUT

^ WINDSHIELD WIPERS - INTERMITTENT WIPERS ERRATIC OR INOPERABLE

^ 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:

^ Transfer Case Mode Switch to become inoperative

^ The 4X4 "Low Range" light to appear dimly lit

^ The intermittent wipers to become erratic or inoperative

^ 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.





2. Attach end of new Vent Hose (F75Z-7A246-M) to fitting, and route the hose up over the top of the transfer case (Figure 1).





3. Attach the clip on the vent hose to the top of the vertical rib on the transfer case extension housing to support the end of the hose (Figure 2).

NOTE
FOR ALL WATER CONCERNS, DRAIN AND REFILL THE TRANSFER CASE WITH FRESH FLUID (XT-2-QDX), AND REPLACE THE VENT HOSE WITH THE REVISED PART.





Parts Block

OTHER APPLICABLE ARTICLES: NONE
SUPERSEDES: 97-11-19
WARRANTY STATUS: Eligible Under The Provisions Of Bumper To Bumper Warranty Coverage

OPERATION DESCRIPTION TIME

011606A Drain And Refill Transfer 1.2 Hrs.
Case, Inspect And/Or
Replace VSS Gear And
Transfer Case Mode
Switch, And Install Vent Kit

DEALER CODING
CONDITION
BASIC PART NO. CODE
7D494 49

OASIS CODES: 202000, 206000, 508000, 508300, 698298