Drivetrain Controls - Int. Warning Messages/DTC P186D
No: LA-308-001Issue: 1
Date: 14 Mar 2006
SECTION: 308-07
Intermittent Transmission Warning Lamps or Message
AFFECTED VEHICLE RANGE:
Land Rover LR3 (LA)
VIN: 5A000360 to 6A357164
CONDITION SUMMARY:
INTERMITTENT TRANSMISSION WARNING LAMPS OR MESSAGE DISPLAYED
A customer may report intermittent multiple warning lamps or a message displayed. The warning lamps may include transmission, Hill Descent Control (HDC), Anti-Lock Brakes (ABS) or Dynamic Stability Control (DSC). The "Special Programs Off" message may also be displayed intermittently. Investigation using Worldwide Diagnostic System (WDS) reveals the Diagnostic Trouble Code (DTC), P186D "transfer case clutch stuck" has been logged at random infrequent intervals.
Cause:
When the ignition is turned on, the transfer box clutch actuator is operated through its normal range of travel to detect its relative position. If a low voltage occurs during this process, the clutch motor will stop before the end of its full range. When the voltage returns, the process begins with the motor starting from the stopped position rather than the beginning of its range. The motor will drive from the stopped position and reach an unexpected early end of range. The motor will then stall on the end stop and log DTC P186D.
NOTE:
If the above problem is not software related, permanent warning lamp illumination and a DTC logged at every ignition cycle will occur.
Action:
Should a customer express concern regarding the random P186D and warning lamp events, refer to the Repair Procedure detailed in this bulletin to update the control module software.
TOOLS:
LRCD13...................WDS CD Disc 13 or later
WARRANTY:
NOTE:
Repair procedures are under constant review, and therefore times are subject to change; those quoted here must be taken as guidance only.
Always refer to DDW to obtain the latest repair time.
DDW requires the use of causal part numbers. Labor only claims must show the causal part number with a quantity of zero.
Normal warranty policy and procedures apply.
REPAIR PROCEDURE
CONFIGURE TRANSFER CASE CONTROL MODULE SOFTWARE NOTE: An EPQR should be submitted for all non-software related issues leading to permanent warning lamp illumination. CAUTION: Connect a suitable battery charger to the vehicle during WDS diagnosis and module configuration.
1. Connect the T4/WDS diagnostic equipment to the vehicle and begin a session.
2. Determine the current software levels of the transfer case control module as follows:
^ Enter vehicle details.
^ Select the "Vehicle Configuration" tab.
^ Select "Module Information."
^ Select "Network Integrity Test."
Note the software part numbers displayed on the WDS screen.
3. Configure the transfer case control module software as follows:
^ Return to "Vehicle Configuration" screen.
^ Select "Module Configuration".
^ If the software part number displayed on the screen is not the same as noted in Step 2 proceed to configure the transfer case control module as follows:
^ Select "Configure Existing Modules".
^ Select "Transfer Case Control Module" from the sub-menu.
^ Check tick-box to continue and follow on-screen instructions.
4. Repeat Step 2 to confirm the software level change.re level change.
5. Exit the WDS session and disconnect the diagnostic equipment from the vehicle.
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