Issue: climate control displays ER. No buttons work, air conditioner is on, flows through last vent (face) chosen as I drive, no fans. All sensors seem to be working properly. Figured it's time to get a dealer level sw readout.

Hi guys,
well it's been an interesting morning. Looks like newer Jaguar dealers do not have the sw to read 1998 XK8s.

Princeton Jaguar (brand new dealer) was nice enough to refer me to a local independent. I'd used them before, Authorized Foreign cars in Flemington, very expensive. Sure enough they have the sw. When I asked if they could read the errors in climate control, he hesitated and said, I better read the whole car, this is connected to the instrument pannel, which is connected to the engine, you don't know what could cause this. Okay I thought and played along, I asked him what a reading would cost, remembering Jaguar dealers quote $165. He came back with $235, wouldn't budge. Though I did get him to agree that if he could not ID the issue it'd be free.

Figured I better keep checking.

Called a few more dealers, no sw available.
Then called the dealer in Allentown. He was nice, obviously didn't have the sw, but talked to me about the symptoms. He's absolutely sure it's the climate controller unit, I couldn't tell if he saw this as a sales opportunity or not. When I thanked him and mentioned they are readily available used, he cautioned me that it may need programming.

Ok so, now I've found 1 dealer 50 miles away with the sw, I assume they'll charge the $165 every other local Jaguar dealer wants for diagnostics, one dealer who is certain it's the display unit (replacement cost $30 used). And one independent who wants $235 to plug her in for sw check (my gut says warning on this one).

I'm leaning to just buying a climate control display given the price, but wanted to see if anyone knows if it's like a module that needs programming. I would not have thought so.

Thanks, John

 

You've probably done this, but can you get the climate control module to tell you what the error(s) is (are)? (I.e. push recirc and auto on the climate controls while you turn the key on, then push auto to see what codes show up).

 

Dale,no I tried . No response at all.
John

 

John,
Too bad. Given that, I don't think they need programming, and they're cheaper than driving over to get a dealer scan. Could be the module, however (also cheap).

 

Have you checked all the fuses/relays? Also, check the ambient/external temp sensor somewhere on the front bumper. Another check would be to open the module and have a look inside for obvious signs of damage, like burnt spots, or corrosion. Check that none of the buttons are permanently stuck on. Also, check the electrical manual and figure out which network this module is on (SCP, ISO?), then check if the other modules on the same network still work. This would rule out a failed bus causing the error display. If in doubt, maybe disconnect the other modules on the same bus one by one to see if it brings life back to this module. If cheap enough out there, would be worth taking a chance on a used module. These diagnostics fees seem high, and the likelihood of producing proper diagnostic is low, i.e. if the box is functionally dead, there will be no smart diagnostic to be had. Unless you have other work to do (like pair up keys or something), I would not travel/pay for this diagnostic alone. Last, at that diagnostic price, you are ready to spend more than one of the recognized handheld devices people talk about (Foxwell, iCarSoft, etc.).

Best of luck, keep us posted.

 

Maybe Motorcarman or NBCat will chime in but I think if you are talking about the climate control panel it is plug and play. That said if you are talking about the climate control module i think it is part of the CAN Bus and will throw a wrong part installed without programming.
My other thought on the situation is that the best course of action is to get a thorough system evaluation. Modules on the CAN Bus may be feeding erroneous information causing downstream problems. I have the ICarsoft unit and it will query most all modules. I just think without definitive information I would just be stumbling blindly in the dark.

 

Great ideas thanks! I feel dumb, been scanning the electrical diagrams for over a week now. Climate control module? Gosh I don't remember seeing it.

Yes I asked about the cc display unit in the dashboard. I thought that connects directly to the air conditioning controller (just checked this is a module), which has 122 separate inputs from the sensors (temp, speed, etc).

I sure didn't know that any handheld device within my means may read this kind of thing!

Bob, NBcat, as mentioned above we'd love to hear what you think.

John

Follow up. I just recanted the diagram to validate the module. I just looked more carefully at the climate control selector in the dashboard. It has 2 data inputs, from ac controller module, two battery inputs, starter input, and dimmer illumination.
This is disheartening seems to point to serial communicationswith ac module, but then again, how could the data signal from the ac module cause all buttons to turn off.

 

I replaced mine in my '97 with one bought on ebay. No programming required, and no "wrong module" error at all. They are pretty cheap. Just make sure you get one that has a good display panel. That was the reason I changed mine- LCD display panel had gone black.

 

Yes, all of the modules are connected by SCP or CAN (or both in the case of the INST) and the data is transmitted by bus to avoid having 3 million wires. Who knows what magic might go on with the SCP bus to make that Er code come up (and maybe turn off all the buttons), but I think a better bet is replacing the display and seeing if that was the problem.

To me, it seems like the other way to see this is to be encouraged that everything is bus connected. Fewer wires to check, and many of the modules are cheap enough to try to fix it by replacing the most 'obvious' thing, here the display.

 

Mind helping me with next steps? Heres the latest:
Yesterday I found a mechanic with sw access. He was cool, ran a reading, hard reboot, and double checked all fuses for me for only $75.

Finding: he could get into every module except the Climate Control module. His conclusion: failed AC Controller.
I explained the symptoms leading up to the total CC failure. Display randomly reset to what my recent studies show to be default/reboot setting or 74 degrees Celsius.

After hearing that he thought aloud, could be a failing/now failed battery connection or ground. There are separate inputs for battery and ground to the controller.

I have picked up a used controller. Will get a new display unit in 4 days.

If you didn't know, replacing the control unit is going to be a PITA. I can only hope I can get to both retaining bolts and get the unit out without having to disassemble ductwork.

As I type this, I realize yes of course I will pin check for both battery and ground connection status at the connector next step. Of course that will not eliminate a bad power supply inside my car's ac controller. Should that show tests ok:

Would you spend the time to swap the controllers first, or from the symptoms figure it's worth waiting 4 or 5 days to just plug in the new used display (15 minute job)?

I appreciate your opinions.

John

 

Depending on what he used (IDS vs something else), hate to possibly be the bearer of bad tidings, but all of mine appear to work correctly, yet my IDS copy never finds/communicates with the climate control module (ERR 0x1407) though it communicates successfully with everything else.

 

;-) that would be my luck ha ha. Thanks Dale.

 

Figure 19.1 Electrical Guide shows the CCM as part of the Serial Data Link (Data Link Connector pins 15 and 7, ECM, CCM, KTM and Adaptive Damping module)

As per Figure 7.1 the Control Module is on the RH side of the A/C unit. The CC Panel is the center console display.

Could be either or??????????

 

Thanks Bob, I'll be putting in the new ac controller tomorrow. Fingers crossed!

John

 

This is now RESOLVED!
It was the air conditioning control module. I really appreciate everyone's
help.

For the record: No the ac control module doesn't need programming.

I will of course write this up in a shorter summary version for folks future reference.

A BIG thanks again,

John

 

Well done....