Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
PDU - Software Updates
1991 Jaguar XJ-6 L6-4.0LSECTION PDU - Software Updates
1-108
DATE
9/99
All
MODEL
All
VIN
New PDU Software - JTP 626/6, JTP 627/7, and JTP 628/4
ISSUE:
New PDU software has been released.
JTP 626/6 replaces 626/5.
JTP 62717 replaces 627/6.
JTP 628/4 replaces 628/3.
ACTION:
Ensure that this software is installed immediately. Retain the previous issues in a secure place as a backup CD-ROM in the event the new software is damaged.
JTP 626/6 - Use for diagnosing 1990-1996 MY XJS and 1990-1994 Sedan Range. There have been no functional changes to this software, the disc has been released to maintain operating system compatibility with the new PDU to PC software. It will also enable the datalogger and JVA applications to take advantage of the new graphing facility.
JTP 62717 - Use for diagnosing 1995-1997 MY Sedan, 1997 MY on XK8 Series, 1998 MY on XJ8 Series, and 2000 MY on S-TYPE. This disc contains all of the existing software plus 2000 MY including XK8 and XJ Series additions:
XK8/XJ Series Rain sensing wiping
Navigation
XK8 ACC (Adaptive Speed Control)
S-TYPE "P" code help information
DTC's fully linked to diagnostic routines
There have been multiple improvements across all systems for 1997-1999 MY For example:
Fuel Pressure Sensor - XJ Series (All Model Years)
The fuel pressure sensor tests have been enhanced. This has been necessary due to the sensor being difficult to access. It is easier to take measurements from an intermediate connector on the harness.
Engine Control Module/Temperature Control Module Cooling Fan - XJ Series Supercharged and all XK8 Model Years.
The engine control module/temperature control module cooling fan tests have been enhanced. The tests are now performed without the use of the current probe. Voltage and resistance measurements are taken from the fusebox.
JTP 628/4 - Use for PDU - PC downloads. A new graphing facility has been introduced on this software, it enables the PC to format graphs as opposed to Bitmap images from PDU. This will improve the layout of printed datalogger and JVA graphs.
DATE
9/99
All
MODEL
All
VIN
New PDU Software - JTP 626/6, JTP 627/7, and JTP 628/4
ISSUE:
New PDU software has been released.
JTP 626/6 replaces 626/5.
JTP 62717 replaces 627/6.
JTP 628/4 replaces 628/3.
ACTION:
Ensure that this software is installed immediately. Retain the previous issues in a secure place as a backup CD-ROM in the event the new software is damaged.
JTP 626/6 - Use for diagnosing 1990-1996 MY XJS and 1990-1994 Sedan Range. There have been no functional changes to this software, the disc has been released to maintain operating system compatibility with the new PDU to PC software. It will also enable the datalogger and JVA applications to take advantage of the new graphing facility.
JTP 62717 - Use for diagnosing 1995-1997 MY Sedan, 1997 MY on XK8 Series, 1998 MY on XJ8 Series, and 2000 MY on S-TYPE. This disc contains all of the existing software plus 2000 MY including XK8 and XJ Series additions:
XK8/XJ Series Rain sensing wiping
Navigation
XK8 ACC (Adaptive Speed Control)
S-TYPE "P" code help information
DTC's fully linked to diagnostic routines
There have been multiple improvements across all systems for 1997-1999 MY For example:
Fuel Pressure Sensor - XJ Series (All Model Years)
The fuel pressure sensor tests have been enhanced. This has been necessary due to the sensor being difficult to access. It is easier to take measurements from an intermediate connector on the harness.
Engine Control Module/Temperature Control Module Cooling Fan - XJ Series Supercharged and all XK8 Model Years.
The engine control module/temperature control module cooling fan tests have been enhanced. The tests are now performed without the use of the current probe. Voltage and resistance measurements are taken from the fusebox.
JTP 628/4 - Use for PDU - PC downloads. A new graphing facility has been introduced on this software, it enables the PC to format graphs as opposed to Bitmap images from PDU. This will improve the layout of printed datalogger and JVA graphs.
RENDER: 1.0x
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.