Land Rover Discovery: Speed Control Speed
Control / Diagnosis and Testing
PRINCIPLES OF OPERATION
For a detailed description of the Speed Control system, refer to the relevant
Description and Operation section in the workshop manual. REFER to:
Speed Control (310-03 Speed Control, Description and Operation).
INSPECTION AND VERIFICATION
CAUTION:
Diagnosis by substitution from a donor vehicle is NOT acceptable.
Substitution of control modules does not guarantee confirmation of a
fault, and may also cause additional faults in the vehicle being tested
and/or the donor vehicle.
NOTES:
- If a control module or a component is suspect and the vehicle
remains under manufacturer warranty, refer to the Warranty Policy
and Procedures manual, or determine if any prior approval
programme is in operation, prior to the installation of a new
module/component.
- When performing voltage or resistance tests, always use a digital
multimeter accurate to three decimal places, and with an up-todate
calibration certificate. When testing resistance always take the
resistance of the digital multimeter leads into account.
- Check and rectify basic faults before beginning diagnostic routines
involving pinpoint tests.
- Verify the customer concern
- Visually inspect for obvious signs of damage and system integrity
Visual Inspection
- If an obvious cause for an observed or reported concern is found,
correct the cause (if possible) before proceeding to the next step
- If the cause is not visually evident, verify the symptom and refer to
the
Symptom Chart, alternatively check for Diagnostic Trouble Codes
(DTCs) and refer to the DTC Index
- Check DDW for open campaigns. Refer to the corresponding bulletins
and SSMs which may be valid for the specific customer complaint and
carry out the recommendations as required
SYMPTOM CHART
SYMPTOM:
Speed control
inhibited/disabled
POSSIBLE
CAUSES:
- Steering
wheel
switchpack
fault
- Engine
system
fault
- Anti-lock
brake
system
fault
ACTION:
- Check the operation of the speed control
switches. Using the Jaguar Land Rover approved
diagnostic equipment, check the body control
module for related DTCs and refer to the relevant
DTC index
- Using the Jaguar Land Rover approved diagnostic
equipment, check the powertrain control module
for related DTCs and refer to the relevant DTC
index
- Using the Jaguar Land Rover approved diagnostic
equipment, check the anti-lock brake system
control module for related DTCs and refer to the
relevant DTC index
SYMPTOM:
Unable to
regulate/adjust
vehicle speed
POSSIBLE
CAUSES:
- Steering
wheel
switchpack
fault
ACTION:
- Check the operation of the speed control
switches. Using the Jaguar Land Rover approved
diagnostic equipment, check the body control
module for related DTCs and refer to the relevant
DTC index
SYMPTOM:
Unable to cancel
speed control
from steering
wheel
POSSIBLE
CAUSES:
- Steering
wheel
switchpack
fault
ACTION:
- Check the operation of the speed control
switches. Using the Jaguar Land Rover approved
diagnostic equipment, check the body control
module for related DTCs and refer to the relevant
DTC index
SYMPTOM:
Unable to cancel
speed control
from brake pedal
POSSIBLE
CAUSES:
ACTION:
- Using the Jaguar Land Rover approved diagnostic
equipment, check the anti-lock brake system
control module for related DTCs and refer to the
relevant DTC index
DTC INDEX
For a list of Diagnostic Trouble Codes (DTCs) that could be logged on this
vehicle, please refer to Section 100-00. REFER to: (100-00 General
Information)
Diagnostic Trouble Code Index - INGENIUM I4 2.0L Diesel, DTC: Engine
Control Module (ECM) B10A2-07 to P034B-76 (Description and Operation),
Diagnostic Trouble Code Index - GTDi 2.0L Petrol/GTDi 2.0L Petrol - SULEV,
DTC: Engine Control Module (ECM) (Description and Operation),
Diagnostic Trouble Code Index - INGENIUM I4 2.0L Diesel, DTC: Engine
Control Module (ECM) B10A2-07 to P034B-76 (Description and Operation),
Diagnostic Trouble Code Index - DTC: Central Junction Box (CJB)
(Description and Operation),
Diagnostic Trouble Code Index - DTC: Anti-lock Braking System Control
Module (ABS) (Description and Operation).
READ NEXT:
REMOVAL
NOTE:
Removal steps in this procedure may contain installation details.
Make the air bag supplemental restraint system (SRS) safe.
Refer to: Standard Workshop Practices (100-00 General
Inform
External Controls
Transmission Control
Switch (G1816637)
Removal and Installation
REMOVAL
NOTES:
Some variation in the illustrations may occur, but the essential
information is always correct.
Rem
SEE MORE:
Do not operate the wipers on a dry
screen.
In freezing or hot conditions, make
sure the wipers have not stuck to
the glass. Use the winter park
position to lift the wiper blades
away from the screen.
Remove any snow, ice or frost from
the windscreen, around the wiper
arms and blades, and the
windscr
SPECIAL TOOL(S)
REMOVAL
CAUTIONS:
Do not allow halfshafts to hang unsupported at one end or joint
damage will occur.
Make sure the halfshaft constant velocity (CV) joints do not over
articulate. Failure to follow this instruction may result in damage to
the CV joints.
Nuts and bolts must