I took my 02R out this morning -- it has been sitting for the last two weeks.

Drove over an hour on the highway and then a few trips around town throughout the day. I stopped at the mail box a while ago and on restart -- "Fail safe engine mode" -- "Trac off". I turned it off and restarted -- it was OK for about a mile and the lights came on -- this time with the CEL.

So, I connected my scanner -- P1122 ...... my book says: TPS - Intermittent low voltage. So something up with the T body.

I cleared the code and then I get -- P1642: Fuel pump monitor circuit - high input. That is a new one on me.


Also, On restarting I am getting an "Er" on the climate control panel with beeping. I got this error message the other time I had a restricted performance problem about a year ago.

Any ideas --- I guess I look at the connections to the Tbody?

I was never able to find any information on the "Er" on the ACC panel.

Have no idea about the Fuel Pump code

 

Get your battery tested first. Any AutoZone, PepBoys Sears can and will do the test for free.

 

You have code P-1122 right. You might check the throttle body connector for corrosion but your car IS NOT among those with the TB recall. unfortunately, the TPS is not available for this engine. In fact there are two TPS sensors that must agree as a safety feature due to the "drive by wire" throttle. You might find a reference for a guy in Tenn who rebuilds these. I would vlean the connector first and see what happens next.

P 1642 indicates a CAN bus failure.

CAN short circuit fault
Control module failure – check for
additional flagged DTC(s) to locate
control module source

Many times that is an atifact of connecting the scanner. Some folks have reported actual can bus failures, but that is rare.

 

I don't think it's a battery problem. The battery is not that old ...... but knowing the Jag's proclivities with low power I'm going to put a booster pac on it just to see.

Looking into the ACC climate error -- it is a #14 error code. This is loss of coolant temperature from the instrument cluster. My information says this should not make it beep (silent error code) ..but mine is beeping.


I cleared all the codes -- and started it up and let it idle for a while. While I was watching the instrument cluster -- the tachometer just dropped to "0" and the "restricted performance" came on. The gas gauge still worked -- Does the tachometer always stop working with "RS". The engine continued to idle normally.


I think it is odd that I am getting this loss of coolant temp in the ACC panel from the cluster.


So my first string of codes P1122 (gas pedal) 1642 / 1797 (TMC- EMC open) 1122/ 1797.

I cleared all of the above - then I get the following with the drop of the tachometer -- 1638 (engine speed/temp missing at cluster) 1642/ 1637 (ABS)/ 1643 (TCM failure)


So I guess I should order a new T Body -- Instrument cluster -- ABS controller - and a TC Module

 

The battery can cause strange things on these cars. Looking at all that is going on in your car Climate Temp, Tach, P1638, P1642, P1637, P1643 P1122. Do yourself a favor and get it tested first.

 

Yeldogt: Those codes all seem to be CAN bus related. It is certainly possible that you are loosing CAN bus traffic. In another thread, the problem was reported to be the ABS system trashing the bus. If it is a CAN bus problem, then any of the modules on the bus could do it. You might try unplugging the connector on the ABS then each of the other CAN modules to see which one is the smoking gun. when you get a module disconneted, and only it reports a code, you have it.
While some problems appear to be voltage related, especially after a car has sat for a spell, you said yours failed after an hour or so, which is plenty of time for the battery to recover. Obviously it would not hurt to measure the voltage.

 

Yesterday, before I tried to start the car I used my scanner and cleared all the codes. Started it up -- all normal - drove around town all day long with no problems. I even took the car over and removed the battery for testing -- tested fine? The battery is just over two years old -- Bosch from Pep Boys -- I have the exact battery in two other cars.


So, I don't know what to do at this point.


I did remove both of the connectors from the T-Body -- both on tight and looked fine. Other than replacing one O2 sensor and the battery, nothing on this car has been touched since new -- now has 50k on it.

I was looking over the service history -- Normal fluid/filter changes. I replaced the front brake pads at 27k -- the dealer refinished the dash wood and replaced the drivers seat leather just as the warranty was to expire. New gas cap. Tires -- many tires.

 

No codes and no problems. Hard to chase a ghost! Your pulling and reinstalling the plugs on the TB may have taken care of a problem but you will not know until it comes up again. It could be the Jaguar Poltergeist!! Welcome to the crowd.

 

Gus --- Unfortunately, I did have the problem after I checked the TBody plugs.

What I find strange is the ACC "Er" -- I had the same thing the one other time the car went into "Restricted Performance". All pointing to a missing coolant temperature output from the instrument cluster?

I can understand the P1122 coming up initially if the TB is the problem -- but I don't understand the flood of additional codes. It's like the whole CAN BUS goes crazy.

And I don't see how a TBody failure could cause this.

 

Recently I have seen several RB due to a poor connection at the TB plug. A few were due to rain / moisture getting into the plug, cleaning it was the right thing. As for the ACC error, I would do a little checking into it. I do not know enough about it. Is your car an 2002 XJR ? See if you can perform this test http://www.gusglikas.com/images/Auto...or%20Codes.pdf Let us know if it works for you and what you come up with…

 

Gus -- That is the test that I performed. The code that came up was #14 -- this refers to the loss of output from the cluster for the coolant temperature to the ACC. It also says that #14 will not cause a "beep" warning but I did get the beep. This was the only code -- I cleared it three times -- it always came back. Now all is well.


I was not clear in my last post. The p1122 points to the petal position -- I guess the TPS sensor in the Tbody. What I was trying to say is I don't understand how this would cause a loss of output from the instrument cluster.

Unless the instrument cluster is a junction point for a lot of sensors/ CAN BUSS - and I have a problem with the instrument pack?

 

A CAN bus failure, if in fact you have such a rare event, will manifest itself by any number of indications. Tghe CAN bus is the main network that allows all of the car's modules to communicate.

 

+1 on Ross comments. A few people cringe when I say clear the codes and see what comes up next. Now that all is well and the codes are clear, have a beer or two and forget it happened. If the problem reoccurs then you need to look into it further. I am not blowing you off, it is hard to find a problem when you do not have it.
PS Drive the car!

 

I understand what the CAN BUS is - what i don't understand is how the components are wired together and what if anything of it goes through the instrument cluster.

I definitely saw the tachometer lose power -- it dropped to zero and RP came up. I have heard of Jaguars needing the cluster replaced -- just don't the the reason for the replacement. I also don't know if when you get a RP warning the engine computer turns off the tachometer -- it may be normal for the tachometer to turn off and I am thinking this is a symptom of some wiring problem.


The first time this happened -- it was late in the evening and I was able to move over and restart -- all was well. This time it did not reset -- so I'm not confident to drive it too far ....certainly not on a bridge or through tunnel.

 

A lot of information for the CAN bus comes from the instrument cluster. When I replaced the dash bulbs with the wrong ones, the cluster didn't power up and I got Er on the ACC with beeps. I can't remember what code came up on the ACC though.

On wiring diagrams, the cluster is somewhat a central CAN bus componet that communicates with a lot of modules.

 

The tach, road speed and engine coolant temp are sent to the ACC module from the instrument pack. I ASSUME the instrument pack gets those from the ECU and the ABS modules via the CAN bus, since no other wires appear to fit that purpose. I have gotten RP for several reasons, including transmission fault and lean burn and misfire and I have never seen the tach misread.
The P1122 does NOT seem to be can bus related, but the others you mentioned previously do. And I agree gus, resetting the codes AFTER WRITING THEM DOEWN makes sense. Most CAN bus error reports are artifacts of connecting the scanner to the BUS circuit. However, since yeldogt has the tach drop out, the ACC faults related to loss of signals from the instrument pack, and multiple codes, I guess he has the real thing. The only way to directly troubleshoot a CAN bus is with a sniffer or a scope and selectively pulling cables until the offending module is found. What you are looking for with complete bus failure is a "screaming modem". All of the devices talk and listen on the same pair. So each transciever has three states for the transmit state- high, low . and open. If the device either trys to send or does not go into open state when others are using the bus, then it will trash the bus and the token cannot be opassed among stations. So, putting a scope on the bus, you are looking for the amplitude and waveshape for a;; packets to look similiar. When you see bad packets, you begin isolating the stations until you find the bad guy.

 

Well -- maybe a look see at the cluster may be in order. I believe the wood trim just pops off ...is it clear whet needs to be done once the trim is off to remove the cluster and see all the connections?

Also -- does anyone know where the other end of the connections from the Tbody end up? I may as well investigate a few other connections.


If my initial problem had thrown an ABS code -- I would suspect the ABS controller board. This is that kind of intermittent problem I'm having. This car is really clean -- its not a car that's had a lot of water around the engine or that has had service where wires and connections would have been removed or damaged.

 

Hello
I started a new thread for the Instrument Cluster Removal & Install:
https://www.jaguarforums.com/forum/j...ter-r-i-57772/

I created 2 PDF files. One for the Cluster and the other for the Cluster Finish Panel (wood trim).

Jim Lombardi

 

Thanks Jim.

In reading the instructions it just mentions releasing the clips for the veneer -- and then to replace them. It does not explain how to actually release them.

Thats a little strange -- do you just pull on the veneer and snap them out?

When I had the dash refinished I did not do the R & R of the veneer. I remember driving over to the dealer and watching them snap them out in a few seconds -- and I was on my way. So it must be easy. I drove around without any wood on the dash for a couple of weeks before it was returned from California.

 

Hi yeldogt
I found this posting on roadfly.com

Re: Squeaky Dashboard
Here is what I did.... not sure which one fixed it but now no squeek

1. Pull off all the wood facier panels
2. Spray Silicon Grease (with the aid of small tube...the non staining kind) into the joints between the top cover of dash and its metal support panel.
3. Push against the instrument cluster gently... mine squeeked. Stop with a littel silicon spray behind the fixing screws/points.
4. Pull out the spring clips that secure the wood facier. Tighten them with plyers.
5.Put 5/8 x 2" draught excluder stip in place of the little felt pads
6. Put tiny bit of vasaline on the lugs that push into the spring clips
7. Reassemble wood facier pushing in tightly

Also our Bob Gauff (motorman) has a posting in the thread on RoadFly.com
Re: Squeaky Dashboard Here is the webpage link:
Squeaky Dashboard


Also found this on the internet:

Remove major gauge module veneer panel for access.
Using a thin plastic lever, carefully release the four veneer panel dowels from fascia clips.

Looks like you use a thin plastic lever get the veneer off at the spring clip locations.

Maybe motorman will post these TSBs for us to view them.

Jim Lombardi