Had something interesting happen and am curious if I should at all be concerned.

I have a 2006 Jaguar XJ8. The air suspension had gone out on it some time last year or so (and, frankly, it had never really been right). I replaced them with coil suspension, which has thus far worked out great. However, they weren't the set that came with the little module that turns off the warning light. Since the old air shocks had been faulty, I was already getting the amber warning light with a warning about the shocks. After replacing the shocks, the amber light remained (of course) and I got a new warning concerning the shocks (since no connection could be made to the old air shocks, I believe). I simply lived with the warning and amber light. A few months ago, I was really sick and ended up in the hospital for about a week. Afterward, I was recovering, which took almost two weeks more. By the time I was healthy enough to start doing things outside the house again, the battery in my Jaguar was dead. Since the battery was about 5 years old, I decided to get a new one. Putting the new battery in went without a hitch and the ol' Jag started right up! I didn't pay attention to the warning lights, to be frank, so I'd been driving the car for about a week when noticed that the amber warning light on the dash WAS GONE! So was the warning about the shocks and shock system! It's not that the warning system is dead or bad. I had a tire lose some air and the warning came right on, telling me which tire to check. Clicking through the display shows everything it always has (mileage, miles per gallon, etc.). But the shock warnings are simply gone, as if the car thinks air shocks are installed.

Now, I like this because it's nice to not have that amber light on. However, why would that warning just suddenly stop? It seems to have coincided with installing the new battery. But I'd had the old battery disconnected a few times before and after reconnecting the old warnings were still there. The car is driving great, so I'm not really worried. But I am curious - why would these warnings simply go away?

 

Check the older threads. Early years, IIRC, the system was less fussy, and the whole subsystem shut up about warnings if the control module was simply pulled (or de-powered).

Your one may have been dislodged or a wire damaged during the battery renewal? H8's are heavy, and awkward to handle.

If you hired it done, a tech might have thought he had CREATED a problem, researched it, pulled the module or such a-purpose to "correct" what might have been thought as 'their' damage, said little about it.

One could ask? Wouldn't hurt to thank him, if so. Steak dinner, not cheap-**** beer?

I didn't mind ignoring the amber light.

Wife asking "what's that light for?" periodically wasn't as easy. She leeched onto the Rover!

 

Thanks for the reply. I had replaced the car battery myself, so no one to offer a steak dinner to (other than myself ). The battery was heavy, sure. But the wires were out of the way before I put the battery in the cradle. So, I don't see how a wire anywhere would have gotten damaged.

 

Well we may accidentally run this mystery down "in parallel", then. Tenth year on the Yuasa H8, replacement had been on-hand for a month or so, cherry-picker nearby if need-be.

Two new aftermarket-not-Bilstein front air struts arrived yesterday afternoon. Meaning they are air-compatible only, but lack the ECATS solenoid in their shock section for electronic modulation.

Which "alarms" .... unless either 'cheated' per-each shock... or the whole module is pulled, back in the boot area.

OEM Bilstein rears will be retained.. for at least another month or three. That precludes disablng my control module, so I'll be "playing with" the module for at least this first go ... before deciding on similar El Cheapo air struts, rear.

Might take me several more days of wrenchly-bation to complete it. Age thing.

If we are blessed, someone with more energy, greater sense of urgency, and/or less patience, might mosey by and enlighten the both of us?

Meanwhile, my bet is still that your module has become de-powered, is no longer able to shout-out an alarm to Ringmaster, cat-herder circus.

Probably possible it was outright fried, too, given your coilovers wouldn't know nor care?

 

"Ringmaster, cat-herder circus."

What an apt description of the ECM or whatever the heck it is.

 

More than thirty years since a succession of "Director of Engineering, North America"' were wielding godawfulcostly protocal analyzers at my beck and call - all of us on Cable & Wireless' dime.. but.. these are sore complex critters, partly because the whole circus was designed by several separate de-facto 'committees' then implemented with many and various bits made by lowest-bidders amongst different suppliers.

As has been said about other stuff:

"The marvel of the thing is not that it works well, but that it even works AT ALL"

Richard Feynman wasn't actually the first to say it, but this fits, too on a "bad cat hair day":

"That isn't right. It isn't even WRONG!"

We JF "deal with that". Same as our first 3.7 billion years.

Just in case anyone forgot whether life or motorcars had the better track record at prevailing.