Hey guys,

Happy Father's Day!

Well, not so much for me. Left the house to pick up my daughter from the gym. Everything was perfect as always -- that is until I took a right turn and, without any warning whatsoever, I lost all power. "Er' message on climate control, engine failure, transmission failure on display. Still had full battery (later confirmed by tow truck operator). Could not raise top, could not shift out of park. Car had to be on skids to get onto the flatbed. Pressed top button so hard it went through the console. Guess I'll find that later.

I presume this is a instantaneous ECM/transmission module failure? I wanted to have the car delivered home, but it will have to lifted off the truck since it cannot be shifted into neutral.

Any thoughts would be appreciated. The has 61,000 miles and has never had one problem -- that is until now.

Thanks!

Madbrad

 

Sorry to hear about your XK8 problems. I got your message. These are different symptoms than when my ECM croaked. Does it still crank? It may be one of the buss fuses in the trunk. Or a ground came off somewhere. If you think it may be the ECM its on the passenger side. Lift the cover with the finger hole by the firewall. Under that its under the large cover closest to the firewall. The smaller cover is for fuses and relays. Remove the 4 screws and lift the cover out. Be careful because the screws are recessed and its easy for them to fall somewhere they will never be seen again. Once the cover is off you will see the ECM, Trans module and a fan. Be careful removing the several plugs going to it. Its just laying in there with no screws or fasteners. A foam rubber pad under the cover (thats likely rotted away long ago) keeps it from moving around.
Oh and my top switch fell into the console last year and I wasn't even trying to push it hard. It just has plastic ridges on it that snap into the hole. I put a small piece of cardboard from a calling card in with it to make it fit tighter so I wouldn't have to do it again soon.


Dave

 

Thanks Dave.

No, it will not crank and it will not come out of park so the car cannot roll. The electricity still works in that the emergency lights will flash and the remote key will work. The gauge cluster works as do all the chimes.

My biggest problem right now is that the car will not roll, so I cannot get it in my garage and I cannot raise the top or rear windows. The tow truck operator was kind enough to lift it off the truck and leave it in his garage overnight. Has to go somewhere tomorrow though.


I read somewhere about a brake switch. Could that cause something this catastrophic?

Thanks again.


Madbrad

 

I would check all fuses including the big ones in the trunk behind the spare. With all this hot weather we've been having something may have taken out a fuse. Use a meter to check the fuses don't rely on just looking at them as sometimes they still look good.


Dave

 

Thanks again Dave. I am heading over there now.

 

Good Luck and hope its something simple and cheap...


Dave

 

Did you remove the plastic star screw next to the shift gate and attempt to move the gear lever by pushing the lock out down with the key?

Did you attempt to raise the top by using the drivers door lock?

 

If the shift cable or switch assembly it goes to failed it could cause those problems but its not likely it would have happened while driving and shutting off the engine. Also the brake switches can cause some weird problems but again its not likely to stop the engine while driving.


Dave

 

Thanks. You saved the day with the star screw idea. The car is now home in the garage where I can plan my attack on the problem.

The top is dead, but I think that is related to the overarching issue. I am beginning to wonder if it could the be the brake light switch. I say that because I had just hit the brake, the cruise control switch will not light, and the car would not shift by hitting the brake.


A friend in the Jag club thinks it is a voltage issue maybe caused by the connection to the positive ground that operates the emergency blinkers in case of an accident. I do know this -- while I was waiting for the tow, my left rear blinker went out and when I checked it, the bulb was blazing hot, which seemed unusual.

Again, many thanks for your help. It saved the day by getting the car home.

On a bright note, the towing company was fantastic and took great car to make the car safe and secured until I got it home.

Madbrad

 

So, what would cause an instant total loss of drive train power, the loss of power to the convertible top, a display of engine failure, transmission failure, stability control failure, inability to use the shifter, and a cruise control failure. I can raise and lower the windows at normal speed and, when I first insert the key, it looks like it is going through its normal paces, but then I get a fast chime and all of the error messages. All of the lights shine brightly.

From what I have heard, this not an ECM problem, brake switch problem, but it could be a battery cell problem. How about throttle body? Having now slept on it, I do remember a brief error message on the display when I first went through the starting routine over the last few starts, but it just flashed and went away. I also remember a clunk from the underbody a few days ago, but I wrote that off since it had no effect. Wheel speed sensor?

I have checked the relevant fuses and they are OK.

Any other thoughts? I cannot see a problem like this one in any post.

Thanks.

Madbrad

 

<p>alternator??</p><p>Inertia switch??</p><p>&nbsp;</p>

 

Are the lights lighting up for the gear shift position? If the cable came loose or the tranny switches are not working right it may cause these problems. If it thinks the car is in gear and not park or neutral that won't let the car crank. It also will not let the top operating if it thinks the car is moving. Use the gear shift lockout bypass method again and with the ignition on move the gear shift and see if the lights follow the gears. Also try starting it in neutral and see if it acts different.


Dave

 

In a very weird way, issues like this are always interesting, even if they are happening to you (me).
So what is new. An OBDII scan reveals not codes but only "link error."

Dave, the shifter lights follow the shift gate, but the lights shudder and blink as if it a so-so connection. It will not crank in neutral or any other selection. Does that help?

To rule out a battery short, I plan to remove the battery and have it tested under load and cell by cell.

Any other thoughts or ideas are appreciated. Again, it will be interesting to find out the answer.

Madbrad

 

Do you have a meter you can check the battery voltage with?
The weird thing is that your engine quit running when whatever failed failed. Things like the brake switches or tranny switch might keep the engine from cranking but not likely to make it stop when already running. If your alternator is working even with a low battery the engine shouldn't have quit.
Even when my serpentine belt left the engine it stayed running although lots of "funny" things happened. It sounds like a power problem of some sort like juice isn't getting somewhere its supposed to. Or something on the data bus came unplugged possibly.

Dave

 

Data bus? Where and what is that?


Thanks Dave!

 

Data bus is part of the way the computer sys talks to the car. Seem to recall that more a programming system then hardware!!?!!?

 

Yes the data bus (can bus) is how all the modules talk to each other.
It might be worth taking the cover off the ECU/TCU bay and carefully reseat all the connectors. Make sure the battery is disconnected when doing so.


Dave

 

Good idea. I plan to take the battery out to have it, so I will check the wiring while it is out.
Thanks again, Dave.

 

Replaced the battery and, not only did it not help, I have a new message "incorrect part fitted". I searched and found a possible instrument pack problem, but that did not affect my MY or VIN.


So, now, I have engine fault, transmission failure, stability control failure, "ER" light on climate control display, and now the incorrect part message. The convertible top will not operate, but all of the lights, windows are bright.


Any ideas?


Thanks.


Madbrad

 

I put my money on that your ECM took a major crap on you. You have a 97, they are well known for them doing some weird ****.