Engine & fuel system
3 documented faults — symptoms, causes and workshop fixes.
Poor throttle response
Cause
Accelerator cable adjuster lost or slipping.
Repair
- Fit modified accelerator cable assembly.
Parts4 parts
| Part | Part number | Qty |
|---|---|---|
| Cable - Range Rover RHD | SSB104040 | 1 |
| Cable - Range Rover LHD | SSB104050 | 1 |
| Cable - Discovery RHD | SSB104300 | 1 |
| Cable - Discovery LHD | ANR5327 | 1 |
Data: Motorwise Workshop. Bulletin 1.
Engine misfire
Poor contact between two halves of data link connector (DLC). Fix: clean and lubricate.
Overview
- Affects
- All models.
- Remedy
- Clean & lubricate
Symptoms
Engine stalls.
Repair steps
- Inspect DLC terminals.
- Adjust female pins to original shape.
- Connect and disconnect plug 3 or 4 times.
- Clean terminals with electrical contact spray.
- Reconnect DLC.
- Lock the two halves of the DLC with a cable tie.
Data: Motorwise Workshop. Bulletin 2.
Poor starting
Poor connections inside the engine bay fuse box.
Overview
- Affects
- Discovery: All models with V8/300Tdi engines.
Symptoms
Alternator warning lamp on. Delayed tachometer operation. Erratic ignition.
Repair steps
- Remove engine bay fuse box inner and outer cover.
- Check battery positive lead screw and alternator output lead screwfor tightness.
- Refit fuse box covers.
Data: Motorwise Workshop. Bulletin 6.
Electrical & ignition
1 documented fault — symptoms, causes and workshop fixes.
Water/dirt ingress into crash sensor harness multi-plugs
Overview
Cause
When the SRS sensor wiring connector disconnected water/dirt seal may become dislodged or lost.
Repair
- Ensure seal is fitted in the wiring harness multi-plug.
- Ensure pointsare aligned.
Data: Motorwise Workshop. Bulletin 3.
Brakes
1 documented fault — symptoms, causes and workshop fixes.
ABS warning lamp illuminated
Overview
- Affects
- All models.
Cause
Excessive wear in front wheel bearings, causing wheel speed sensor to be moved out of its correct position.
Excessive wear in rear wheel bearings, causing wheel speed sensor to be moved out of its correct position.
Faulty ABS control module.
Repair steps
- Check front wheel bearings for excessive wear and replace if necessary.
- Adjust rear wheel bearings.
- Re-position wheel speed sensors, replace if necessary.
- Check ABS control module, replace if necessary.
- Access ABS control module fault memory and erase trouble codes.
Data: Motorwise Workshop. Bulletin 7.
Body & trim
2 documented faults — symptoms, causes and workshop fixes.
Excessive noise from rear seat backs whilst driving
Cause
Excessive play between stops on seat frame.
Repair
- Fit anti-rattle washer kit.
Parts1 part
| Part | Part number | Qty |
|---|---|---|
| Anti-rattle washer kit | HTP 100080 | 1 |
Data: Motorwise Workshop. Bulletin 8.
Water ingress into spare wheel well
Tailgate seal leaking. Fix: fit a new part.
Overview
- Affects
- All models.
- Remedy
- Fit new part
Repair steps
- Remove and discard tailgate seal.
- Apply sealant to tailgate flange.
- Fit new tailgate seal.
Data: Motorwise Workshop. Bulletin 9.
Other
2 documented faults — symptoms, causes and workshop fixes.
Alloy wheels difficult to remove
Overview
- Affects
- All models with alloy wheels, →03/01.
- Remedy
- Clean & lubricate
- Parts
- 1 part
Cause
Corrosion between hub spigot and wheel centre.
Repair
- Clean corrosion from wheel contact surfaces.
- Apply anti-seize grease to wheel contact surfaces.
Parts1 part
| Part | Part number | Qty |
|---|---|---|
| Anti-seize grease | RYL105020L | 1 |
Data: Motorwise Workshop. Bulletin 4.
Unreliable spark plug operation
Poor reliability of spark plugs.
Overview
- Affects
- All models.
Symptoms
Short spark plug service life.
Repair steps
- Fit RN11YCC spark plugs.
- Replace spark plugs at 40.000 kilometre service intervals.
- Replace spark plugs at 24.000 mile service intervals.
Parts
| Part | Part number | Qty |
|---|---|---|
| Spark plug - RN11YCC | ERR 3799 | 8 |
Data: Motorwise Workshop. Bulletin 5.
Glossary
Technical terms used in this guide.
- VIN
- Vehicle identification number — 17 characters, found at the base of the windscreen and on the V5C logbook
- ABS
- Anti-lock braking system — stops the wheels locking under hard braking
- Trouble Codes
- Standardised fault codes stored by the engine control module, read with a diagnostic tool
- DLC
- Data link connector — the diagnostic socket a scan tool plugs into
- SRS
- Supplementary restraint system — the airbags and seat-belt pretensioners
- Anti-Seize
- Grease that stops mating parts (like a wheel on a hub) from corroding together
- Control Module
- A control unit for one of the vehicle's systems (engine, gearbox, brakes, body, and so on)
- Fault Memory
- The list of stored trouble codes in a control module
- Hub Spigot
- The raised centre of the hub that locates the wheel
- Multi-Plug
- A multi-pin electrical connector on a wiring harness
- Wheel Speed Sensor
- A sensor at each wheel used by ABS and stability control
- Wiring Harness
- The bundled cables that carry power and signals around the vehicle
- Alternator
- The unit that charges the battery while the engine is running
Frequently asked questions
What are the common faults with the Land Rover Discovery 3.9?
This guide contains nine workshop bulletins for the Land Rover Discovery 3.9. Of these, three concern the engine and fuel system and two the body and trim. Symptoms, causes, repair steps and part numbers are shown where supplied.
Does every Land Rover Discovery 3.9 have these faults?
No. These are patterns documented across the model by workshops, not predictions for an individual vehicle. Where a fault applies only to certain vehicles or VIN ranges, that is listed with the fault.
Can I check for Land Rover Discovery 3.9 faults myself?
Many of them. The documented symptoms can be seen, heard or felt during a test drive.