REM Module throwing errors?
 

I have a 2004 XJ8 VDP, and recently had a new headliner fitted. I noticed after about 2 weeks the sunroof did not open and close properly and so I ran my Foxwell scanner through the system and on "Module 11, REM" as seen in the attachments were all RED.

My concern is that its showing the sliding roof switches "Short circuit to ground"and I was wondering if this condition would run my battery down?

Last week I did put in a new battery since the old one was from March 2011 and was not holding its charge, obviously I do not want to damage the new battery!

Another concern is it is showing problems with the fuel pump...the car starts and runs good?

It shows problems with the rear light which does not exist...all lights work OK?

Is it possible that the REM Module itself is faulty and giving off sperious signals?

Any help would be greatly appreciated, David

+1 to listen opinions and share experience re fuel pumps control out of range/non working when requested. I have same errors since I bought the car. I changed all pumps as I got error with secondary pump in addition.. nothing changed as well as car starts and running good. However error with secondary pump disappeared.

I have some problems with my fuel pumps, I have a 2003 xjr which has the same pumps as your car I think.
Could you tell me where you sourced the replacement fuel pumps and their specification?

You had a new headliner fitted and shortly after problems with the sunroof closing which is in the same area.

I think you should investigate roof motor wiring.

I got the same DTCs, after my headliner was replaced - just out of curiosity, did you ever found out if there was a problem with your REM?

Did you clear all codes and then do a system reset? If the car was turned on while everything was disconnected you would get many of these faults.

I did clear all the codes (multiple times) after the headliner removal but the codes keep coming back.
The system reset is done by connecting both battery cables for some seconds right? If so, then I did that as well :D

Unlikely shorts to ground
 

I believe the trigger for 'short to ground' occurs when the voltage check by the module is below an expected value. It is not necessarily a true short at all.
With so many of these errors I would expect there is probably a bad ground in your system. The bad ground causes a large voltage drop across that connection. The comm errors also appear when the voltage drops below a certain level and is also affected by bad grounds - comm errors can occur with the voltage as high as 12.2v. Both my GEM and REM drop out around that voltage.

This means I should check all the ground studs in the back of the car :icon_nut:

That would be a good place to start. Don't forget both battery posts as well - they may look OK but clean them anyway. Then the two -ve connections to the body, on the battery -ve cable.
Then check everything that is operated by the SCP bus to see if there is a break somewhere in that circuit. The roof is controlled by that as well as many others. There is a test somewhere in Jags manuals that indicates that if you can do universal open and close from the fob, and everything works, the SCP network is completely functional. Been a while since I read that but I think that is what is said.

Thanks Edward, I really appreciate it!

Originally Posted by Hendirk View Post
I did clear all the codes (multiple times) after the headliner removal but the codes keep coming back.
The system reset is done by connecting both battery cables for some seconds right? If so, then I did that as well https://www.jaguarforums.com/forum/i...es/biggrin.gif

Believe that you will need a Jaguar type of reader to clear the codes.
But i could be wrong

I'm sure you are right. But that's why I used SDD 130 on an old Win XP Laptop to read and clear all codes

Did you get this fixed? When you cleared the codes did you go back to the sessions tab and read from there or did you use the reread codes just below the erase all codes. Jag says to go back to session tab and not use the reread.

I did not had the time yet but when I remember it correctly, I did not go back to the sessions tab but simply used the reread button on the same page :S I will try to erase the codes again when I'm at the workshop, thanks for the advice :)