Air suspension problem

[joey]

P38 Heater TSB Part 2
SUBJECT:
PRIDE - HVAC Printed Circuit Board Check/Replace

MODEL:
Range Rover 4.0/4.6

AFFECTED VEHICLES: LP SA302295 to TA344173
LH
LJ
LD

DETAIL







Some Range Rovers may experience poor operation of the heating and ventilation unit To overcome these concerns, Land Rover has introduced a new Heating and Air Conditioning Control logic. The new control software has been fitted on the assembly line and produces a safe VIN of TA344173. Any vehicle after this VIN will have the new control software fitted upon assembly.

A fix has been designed which involves the replacement of the PC board in the control unit. Use the following procedure to replace the PC board.

The diagnostic steps and repair procedures detailed on this bulletin were developed as an element of the Land Rover Way OPERATION PRIDE. This TIB provides a library location for PRIDE information within the Land Rover North America technical literature system.

ACTION REQUIRED

Upon customer complaint for the symptoms outlined, perform the specified repairs. Reference should also be made to bulletin 86/02/96/US (Exterior Temperature Reading Incorrect) prior to replacing the control panel.

PARTS INFORMATION

STC 3702K HVAC Circuit Board

LRNASTATK Anti-static Mat Kit

PROCEDURE

Perform the diagnostic procedures and repairs as outlined for the repair of HVAC control units.

WARRANTY:

Normal warranty procedures and policies apply.

COMP. CODE:

6Y1U

SRO:

80.10.02 - Time 0.35 hr.
Remove HVAC control and inspect

80.10.89.27 - Time 0.55 hr.
Remove HVAC control, inspect and replace circuit board

NOTE: Times and operation descriptions are modification of PRIDE manual information.

SYMPTOMS:

Poor operation of the heating and ventilation unit can be categorized by the following symptoms:

Symptom 1:

Poor performance of heating and ventilation system in automatic mode. Specifically, insufficient responsiveness to achieve and maintain selected cabin temperature after start-up in hot ambient conditions.

Symptom 2:

Delay after start-up in hot ambient conditions before cooled air is supplied.

Symptom 3:

Inaccurate exterior-temperature readout, especially after hot soak.

To overcome these concerns Land Rover is introducing a new Heater and Air Conditioning Control Panel with the following changes to overcome the above symptoms:

Symptom 1:

More aggressive fan speed control and revised dynamic performance strategy (including improved recirculation logic) to provide optimum performance in achieving and maintaining selected cabin temperature.

Symptom 2:

Logic changes within the unit eliminate the delay.

Symptom 3:

High temperature accuracy is improved due to changes made in the recirculation within the unit.

NOTE: For more information on system characteristics, how the system works and diagnostics, see the HVAC specification document published with Operation PRIDE.

Refer to the Workshop Manual section 80, HVAC Controls, for removal instructions.

(Refer to this bulletin for the PC board replacement instructions)

 

[joey]

p38 Heater TSB Part 3
Date: 02/22/02


Improved HVAC Temperature Sensor

AFFECTED VEHICLE RANGE:

Range Rover (LP) Up to 1A450120

SITUATION:

INCONSISTENT IN-VEHICLE TEMPERATURES

The customer may complain of too much heat in cold conditions or being too cold in hot conditions. The in-car temperature sensor is ventilated by a miniature fan, which draws air from inside the vehicle. The ****** bearing of the fan can wear prematurely, causing the fan to become stiff or sluggish. The starting torque of the motor is low, permitting the motor to sit in a stalled state. When the fan fails the sensor is not ventilated and the fascia temperature is sensed instead of the in-car temperature.

RESOLUTION:

REPLACE FAULTY IN-CAR TEMPERATURE SENSOR

NOTE: The condition described in this TIB is NOT the "32 degree/snowflake" issue dealt with in TIB 80/01/98/NAS and Parts Bulletin PGI99-07. If a Range Rover HVAC appears to overheat or overcool intermittently and it has the latest head unit, suspect the aspirator.

Where a customer complaint of the above is confirmed, replace the temperature sensor with a new part.

PARTS INFORMATION:

JTF000030 Temperature sensor (includes fan) Qty 1

WARRANTY CLAIMS:

82.20.93 Time 0.60 hrs.
Install replacement fan/sensor assembly

FAULT CODE: D

Normal warranty policy and procedures apply.
Material allowance is included in labor operation.

REPAIR PROCEDURE

REPLACE FAN SENSOR UNIT







1. Use the smoke from an extinguished match or similar source to determine that the sensor motor has stalled.

2. Refer to Workshop Manual, Air Conditioning, section 82.20.93 and perform the fan/sensor replacement repair.

 

[BrettSanDiego]

Alright. Useful info. Where do you get access to the TSB's? alldatadiy.com? I've got it for another car, but haven't signed up for the Rover.

Thanks,
Brett

 

[joey]

I just search.... I have about 200 links for different rover info.... Parts/accessories/repair/general info..... etc.

 

[Mrossfly]

No kidding...careful what you wish for. These responses are awsome.

 

[Mrossfly]

Slow Pump-Up after Leaving Overnight:
In theory, even if the unintelligent ECU has lowered the vehicle to the bump stops overnight, the non-return valves in the valve block should ensure that enough air remains in the tank to pump it up again immediately in the morning. If this does not happen, and it takes ages for the system to pump up to normal height in the morning, air is probably leaking from the line from the tank to the valve block (usually at the connection to the valve block). If not, the valves inside the valve block are probably leaking; as of this writing there is no known solution for this other than to replace the $800 valve block.

 

[joey]

If you want it fix back to original, then it will cost you big time..... or you can replace the EAS with Spring for less than half the cost and never worrry again.

As I said in my first post.... Springs are cheap.

 

[Mrossfly]

All signs point to doing the conversion to shocks and springs rather than repairing the air suspension system. Range Rover is quoting me $2600.00 to do the job with the "better kit".

Is the kit a Range Rover or after market product?
Am I safe letting my local foreign auto shop do the conversion?
What is a reasonable price to have this done.

Thanks so much for all of you valuable time and information.

 

[joey]

Kind of an aftermarket item

Anyone that can change shocks and springs (including you if mechanically inclined) could do the job.

https://www.roverparts.com/Parts/9520LBHD.cfm

 

[Mrossfly]

Joey, I contacted them and they reccomend the regular kit with Bilstein shocks. These guys high quality?