Verification Of Transmission Sensor Faults (44/01/05/NAS)

Publication date: 2005-03-07
Reference number: 44/01/05/NAS

VERIFICATION OF TRANSMISSION SENSOR FAULTS

TECHNICAL SERVICE BULLETIN

Reference Number(s): 44/01/05/NAS, LN307, Date of Issue: March 07, 2005

LAND ROVER:	Freelander (LN)
REFERENCE:	SB 125
ISSUE:	1
SECTION:	Clutch, Transmission, Differential
AFFECTED VEHICLES:	Freelander (LN) Transmission serial number 0600001 -1812986

SITUATION:

SHIFT QUALITY CONCERNS FROM SENSOR DETERIORATION

A condition can develop which results in harsh transmission shifts, the possibility of the transmission defaulting to limp-home mode/restricted performance mode and a MIL illumination with logged fault codes P0715, P0720 or P1715.

The likely reason for this type of event is that during the manufacture of the speed sensor the soldering process may have burned off the enamel protective coating on the wire, leaving the copper cable core exposed. Automatic Transmission Fluid (ATF) seeps past the connector blades through capillary action and enter the sensor body, coating the wire. The hot ATF chemical attack of the exposed cable causes resistance to increase, followed by sensor failure. The corrosion accelerates as the ATF temperature increases.

RESOLUTION:

IDENTIFY AFFECTED SENSOR

An effective containment action has been introduced to address the sensor contamination issue both in production and through Service Action B125. This Technical Information Bulletin provides guidance to identify a faulty Output (Vehicle) speed sensor on an individual transmission within the specified Serial Number range that may exhibit the described symptoms.

PARTS INFORMATION:

Information Only

DDW WARRANTY CLAIMS:

Information Only

NOTE: The diagnostic process outlined as guidance in this TIB will lead to performance of either Option A or Option C of Service Action B125 if the Service Action remains OPEN on the vehicle being diagnosed.

The inspection steps could also lead to a transmission replacement following normal warranty procedures. In addition, Option A of B125 will be claimed if Service Action B125 remains OPEN on the vehicle being diagnosed.

Normal warranty policy and procedures apply.

Material allowance is included in labor operation.

REPAIR PROCEDURE

INVESTIGATE SENSOR RESISTANCE

Confirm Transmission Serial Number is within applicable range (0600001 to 1812986).
Locate Connector C0243 (Solenoid-Gearbox Connector), located front left-hand side of engine compartment. (Fig 1 )

Fig 1: Locating Connectors

Refer to pin identification table and Fig 2 . Perform resistance checks to identify possible 'open circuit' states.

PIN IDENTIFICATION

PINS	PARTS NAME
1 to 2	Turbine speed sensor
3 to 4	Intermediate speed sensor
5 to 6	Output (Vehicle) speed sensor

Fig 2: Performing Resistance Checks

CAUTION: The Output (Vehicle) speed sensor is not serviceable. Service Action B125 only addresses issues with the Turbine and Intermediate speed sensors.

If either the Intermediate or Turbine speed sensors is identified as "pen circuit," perform the Service Action B125.
NOTE: GTR lookup sequence is as follows:
GTR Home > NAS > Service Information/ LN Freelander 2002 > Workshop Manuals > Service Procedures > Bookmark "AUTOMATIC GEARBOX - JATCO 44-1" > TOC "REPAIRS/Gearbox -KV6" link
If the Output (Vehicle) speed sensor is identified as an "open circuit," refer to GTR section 44.20.02.99 and install a new Automatic Transmission.
Claim the correct Option for Service Action B125 if that Service Action remains open on the vehicle:
- Option A if inspection leads to transmission replacement. This clears the Warranty Record.
- Option C if inspection leads to performance of the Service Action B125 procedure.