Seat/Steering/Mirror Memory System - Diagnostics: Overview
501-51DATE
04/02
V8 XJ Series/XK
MODEL
1997 MY-ON XK Range
1998 MY-ON V8 XJ Series
VIN
001001-ON
812256-ON
Memory Systems - Driver's Seat, Steering Column, Door Mirrors - Diagnostics
Issue:
This Technical Bulletin provides diagnostic procedures for the memory system which controls the seat, steering column, and door mirror memory.
In most cases, a memory recall problem is not caused by the memory system itself. There is often an electrical or mechanical fault with another component, resulting in the memory not recalling as expected.
Action:
Information to aid with diagnosing faults:
Note:
This bulletin includes a copy of the Frequently Asked Question (FAQ) ref 2241 XK vehicles and ref 2242 V8 XJ vehicles from the Electronic Product Quality Report (EPQR) system. The information in the FAQ may be needed to help diagnose the faults.
Please read the "Key elements of memory systems" in the Technical Bulletin for help on what memory functions the vehicle has. The table includes information on the modules used to store memory, the controls used to store and recall memory, and the easy entry/exit function.
When the customer first reports the concern it is recommended that you complete a 'customer memory system questionnaire to record all details of the concern.
Whenever possible identify the exact axis that is not recalling correctly, as it will be needed to help identify the cause of the fault. You should also identify if the memory fails to recall correctly during.
1. Easy entry/easy exit mode.
2. Memory recall from drivers door switch pack.
3. Memory recall from key fob.
4. Programming of memory system.
Outline of bulletin contents
Customer Concern Section
Easy entry/easy exit problem. Flow chart 1
Memory recall problem from driver door
switch pack. Flow chart 2
Memory recall problem when using
key fob. Flow chart 3
Diagnosis of issues.
Other information
Other sources of information to aid diagnosis.
Key elements of memory systems.
Memory system - customer questionnaire.
FAQ 2241
FAQ 2242
How to check if the easy entry / easy exit function is working correctly see - Flow chart 1.
Things to know about the easy/exit function:
1. On V8 XJ vehicles, if the seat is within approximately 50 mm of its rear most travel the seat may not move during easy entry/exit mode, as this position is outside the defined operating range for this function.
2. On V8 XJ vehicles, if the key fob has not been programmed with memory settings, and it is used to unlock the vehicle, the seat and steering column will recall to the last position you set and not the memorized position.
3. On V8 XJ and XK vehicles, if any of the manual switch packs (directional controls) are operated during easy entry/exit mode the function will cease.
Diagnosis A
One or more axis does not move correctly when operating the applicable switch-pack If this happens the problem may not be related to the memory system. If one axis does not recall correctly it may be caused by a mechanical or electrical problem with that part of the system rather than memory recall.
Check points:
1 If a complete system will not move then check the relevant fuses.
2 Chaffed or damaged hamesses.
3 Pins backed out of connectors.
4 Poor connections to motors, potentiometers, and modules.
5 Short or open circuits.
6 Motors being strained or overloaded.
7 Bent, buckled, or damaged mechanisms.
8 Worn mechanisms.
9 Poor connections to the controlling switch pack.
10 Switch pack buttons not operating correctly.
11 Check the type of seat that is fitted - perhaps the customer thinks the seat has more movements than it actually has.
Diagnosis B - No memory recall from the switch pack
If, after pressing the memory recall button on the switch pack the seat, door mirrors, steering column, and head-restraint did not move at all, the memory system does not appear to be working.
Note:
Look at each part of the system carefully for any signs of movement - if part of a system moves even slightly then the memory system is trying to recall the stored settings. If this is the case the memory system is working, but not all positions are recalling correctly.
Things to check if there is no memory recall at all:
1 Is the driver door switch pack faulty? (Look for buttons sticking, water ingress, do the memory recall buttons appear to work OK)
2 Are the fuses for the memory system OK?
3 Has memory been programmed to a switch pack button?
4 Is the driver door module working correctly?
5 Are the connections and harnesses to the driver door module OK?
6 V8 XJ vehicles only: Is the driver side rear door module working correctly/are the connections and harnesses OK?
7 Is the BPM working?
Diagnosis C - One or more axis does not return to the memorized position
If at least one axis moves when the memory is recalled, either from the driver door switch pack or the key fob, then the memory system is working. The problem is therefore a mechanical or electrical problem with the affected axis, or a problem with one of the modules.
Note:
It is not possible for a module to intermittently lose its memory and then re-gain it. Intermittent memory recall problems will be caused by something other than the memory system.
Check Points:
1 A chaffed or damaged harness.
2 Loose or backed out pins to modules and the corresponding harnesses connectors.
3 Poor connections to motors or potentiometers.
4 Potentiometers not functioning correctly - use data logger to check the output of the potentiometers.
5 Potentiometer may be out of range - this may happen if a memory position is towards the maximum travel of an axis.
6 Poor connections to switch packs.
7 Short or open circuits on harnesses.
8 Physical damage or wear of mechanical components such as slides, linkages, or gears.
Diagnosis D - The memory system will not store the required positions (no confirmation chime from the system}
When programming the memory system, a chime should be heard when the "M" memory button is pressed to confirm that the memory has been stored.
If this does not happen check:
All conditions required to program the memory system are correct. Refer to "other sources of information" on where to find details on programming the memory system.
If the conditions have been met diagnosis of the components will be required.
Check points:
1 Connections to the driver door switch pack.
2 Correct operation of the switch pack buttons.
3 Connections to the driver front door module.
4 Harness integrity to the switch pack and door module.
5 Connections to the body processor module.
6 Correct operation of the BPM.
7 V8 XJ vehicles only - correct operations and connections to the driver rear door module.
Diagnosis E - Key fob does not recall memory settings
This section deals with the key fob not recalling any memory positions - the seat, steering column, door mirrors, and head restraints do not move at all. If this is the case it may be a key fob issue rather than a memory issue.
Check points:
1 Does the locking and security system work correctly? If it does not it may indicate that the SLM is the cause of the problem.
2 Has the key fob been programmed with memory setting?
3 When programming the fob does the vehicle give a chime to confirm the memory has been assigned to the fob?
4 Is the key fob battery OK?
Other sources of information to aid diagnosis:
WDS can be used in data logger or guided diagnostics modes to help pinpoint the source of concern.
Technical Bulletin: 501-35 - V8 XJ memory front seat potentiometer adjustment or replacement.
Frequently Asked Questions (FAQ) from the Electronic Product Quality Report (EPQR) system (shown in this bulletin).
1 2241 - XK memory system.
2 2242- V8 XJ memory system.
Key elements of memory systems on V8 XJ and XK vehicles.
V8 XJ Drivers Rear Door Module
^ The driver's door switch pack is connected to the Driver's Rear Door Module (DRDM) on V8 XJ vehicles.
^ The DRDM sends a 'set memory' command to the Driver Door Module (DDM) and receives the memory recall command from the driver door switch pack.
^ The DRDM is responsible for checking that the operational conditions are correct for memory operations to occur.
It also checks the key fob identification when memory recall is requested from the key fob, via the SLM.