Automatic Temperature Control Fault Display Correction (82/01/03/NAS)

Publication date: 2004-02-27
Reference number: 82/01/03/NAS

AUTOMATIC TEMPERATURE CONTROL FAULT DISPLAY CORRECTION

TECHNICAL SERVICE BULLETIN

Reference Number(s): 82/01/03/NAS, Date of Issue: 27 February, 2004

LAND ROVER:	Range Rover (LP)
ISSUE:	1

AFFECTED VEHICLE RANGE

Range Rover (LP): up to 2A427128

SITUATION

'HANDBOOK SYMBOL' ILLUMINATED ON THE ATC DISPLAY

When the coolant temperature reaches 97°C (207°F), and stays at or above that temperature for ten minutes, the Automatic Temperature Control (ATC) diagnostic system will illuminate the 'handbook symbol' on the ATC display. The diagnostic fault code in the ATC panel software is set too low for normal vehicle operating conditions in very hot climates.

RESOLUTION

INSTALL RESISTOR TO ADJUST ATC INPUT

NOTE: Installation of the resistor will "adjust" the displayed output temperature seen in real-time T4 monitoring. Comparing the ATC sensor output after the modification with other coolant temperature information in real time can be misleading.

CAUTION: It is important to verify that there is not a mechanical cause for high coolant temperatures. Inspections for leaks and verification of the coolant level as well as proper fan and thermostat operation should all be verified.

Should a customer express concern regarding the appearance of the "handbook" symbol during hot weather operation, the DTCs should be examined to determine if the vehicle has a fault for the heater core temperature sensor. If that fault is flagged on vehicles built before the above VIN, follow the rectification procedure in this TIB to install an in-line resistor link lead between the heater temperature sensor and the electrical harness.

Also refer to TIB 80/03/96/US HEATER CORE SENSOR REPLACEMENT for information relating to intermittent operation of early vehicle heater core sensors. Sensor date codes should be "46" (April 1996) or higher.

PARTS INFORMATION

YMQ501010 .... Link lead Qty 1

AS400 WARRANTY CLAIMS (CANADA ONLY)

82.20.94 .... Time 0.10 hrs.

Install ATC system wiring resistor link lead

FAULT CODE: A

DDW WARRANTY CLAIMS

DDW requires the use of causal part numbers. Labor only claims must show the causal part number with a quantity of zero.

DDW Warranty Claims

Description	SRO	Time (Hours)	Condition Code	Causal Part
Install link lead	82.20.94	0.10	42	JFC102550

Normal warranty policy and procedures apply.

Material allowance is included in labor operation.

REPAIR PROCEDURE

INSTALL LINK LEAD RESISTOR

Refer to RAVE Workshop Manual section 82.20.94 and perform steps 1-5 to gain access to the heater temperature sensor.
Disconnect the heater temperature sensor multi-plug. (Arrowed in Fig 1 ).

Fig 1: Locating Heater Temperature Sensor Multi-Plug
Courtesy of LAND ROVER NORTH AMERICA, INC.
Connect the link lead (YMQ501010) to the heater temperature sensor and electrical harness (Fig 2 ).

Fig 2: Connect The Link Lead To The Heater Temperature Sensor And Electrical Harness
Courtesy of LAND ROVER NORTH AMERICA, INC.
Reverse the Workshop Manual section 82.20.94 removal procedures steps 1-5, and install the removed components.