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Difficult Differential Lock Selection (41/02/98/NAS)

Publication date: 1998-10-23
Reference number: 41/02/98/NAS

DIFFICULT DIFFERENTIAL LOCK SELECTION

DIFFICULT DIFFERENTIAL LOCK SELECTION

TECHNICAL SERVICE BULLETIN

Reference Number(s): 41/02/98/NAS, Date of Issue:  October 23, 1998
LAND ROVER: 1995-1998 Discovery; 1997 Defender
ISSUE: 1
SECTION: Gearbox
AFFECTED VEHICLES: Discovery (LJ) - up to WA794728; Defender (LD) - All

SITUATION

INABILITY TO SELECT OR DISENGAGE DIFFERENTIAL LOCK

Difficulty may be experienced engaging or disengaging the differential lock. The differential lock warning light may operate normally, despite the engagement difficulties.

RESOLUTION

NEW SWITCH LOCATION SYSTEM ELIMINATES INTERFERENCE WITH LOCK MECHANISM

Use of a switch spacer and new tightening specifications ensures that the differential lock warning light switch is properly positioned and will not interfere with differential lock engagement or disengagement.

PARTS INFORMATION

PARTS INFORMATION

P/N Description
PRC2911 Switch, differential lock warning light
UYF100160 Spacer, differential lock warning light switch
LRN21456 Loctite(R) 577 Thread sealant compound

WARRANTY CLAIMS

WARRANTY CLAIMS

SRO Model Description Time
41.20.34 Discovery Replace differential lock warning light switch with new component 1.75 hrs.
--- Defender Replace differential lock warning light switch with new component 1.00 hr.

FAULT CODE: U

Normal warranty policy and procedures apply.

REPAIR PROCEDURE

INSTALLATION OF SPACER WITH REPLACEMENT SWITCH

NOTE: Any time the differential lock warning light switch is replaced, use of the newly introduced spacer will ensure proper adjustment.
  1. Determine that warning light switch is the cause of differential lock engagement difficulties as follows:
    • Back out the switch slightly.
    • Move the differential lock lever to check engagement.
  2. If the switch is the cause, remove the old switch.
  3. Orient spacer (UYF100160) with recess toward switch head (Fig 1 ).
    Fig 1: Orienting Spacer
    G00287607
  4. Install spacer onto replacement switch (PRC2911) and tighten until snug against the head with no visible gap (Fig 2 ).
    Fig 2: Installing Spacer
    G00287608
  5. Apply Loctite(R) 577 to switch threads and install on front output housing (Fig 3 ).
    Fig 3: Installing Switch Head
    G00287609
  6. Hand tighten switch until contact is made between the spacer and the housing.
    CAUTION: Apply torque to the spacer, not to the switch. Damage to the switch may result if incorrect torque procedures are followed.
  7. Place wrench on spacer and torque spacer/switch assembly to 11 N.m (100 lbf.in.).