| Author | Message | ||
     Jonathan Hensel (Nanoscale) New Member Username: Nanoscale Post Number: 29 Registered: 03-2003 |
So, can your computer learn bad habits over time? I have heard about poor running conditions after disconnecting power during relearn. Mine seems to have to learned how to perform. I bought my disco off a lady (95 D1, 62k) who rarely even got on the freeway, or even hit 60mph for that matter. It was pristine but wimpy. I noticed that it shifted out of first wayyyy to early (~5 mph), and out of second a bit early, eating my acceleration. Disconnected it last weekend and rebuilt the alternator, and now it shifts really nice and late, lets me hit a nice peak to hit onramps. Does it just need a fresh leadfoot to teach it a lesson? | ||
| Erik G. Burrows (Erik) Member Username: Erik Post Number: 195 Registered: 04-2002 |
Actually, my dealer told me that driving it 'hard' right after a long disconnect (computer reset) will teach it to be better prepared for hard driving. | ||
| Milan (Milan) Member Username: Milan Post Number: 172 Registered: 10-2002 |
Doesn't D1 have manual valvebody transmission? How would shift points be affected by disconnecting the battery? | ||
| Land Rover Certified Used A**hole (Jason) Senior Member Username: Jason Post Number: 434 Registered: 04-2002 |
No kidding... It has a cable kick-down linkage as well. Here's a test...drive it gingerly like you are a Sunday driver. It should shift into second before or around 10 mph. Now floor it from a stop, it should stay in first gear until 3500 or 4000 rpm. If you are at wide-open throttle, the kick-down cable keeps the transmission from shifting into the next gear until it hits the transmission's governor. | ||
| Paul T. Schram (Paulschram) Senior Member Username: Paulschram Post Number: 1242 Registered: 02-2002 |
Unnecessarily disconnecting the battery on a Land Rover is not a good thing. To begin with, the OBD-I vehicles have few settings that are determined by run-start cycles. But, there are many things that can be permanently damaged by doing this, like the ABS ECU and the air-bag circuitry. Liked happened to mine! Although Land Rover states in their workshop manuals to do so, doing it can result in a trip to the dealer to have lights reset and occasionally, fatal faults can be caused. Newer Land Rovers (OBD-II) suffer even moreso from having battery power disconnected, to the point that disconnecting the battery can cause catastrophic failures. The reasoning that has been explained to me is that they expect the batteries to last long enough that it wouldn't cause problems, and also, they expect folks to take their trucks to the dealer for battery replacements (and resetting of dash lights). | ||
| Kevin Novakowski (Kln) New Member Username: Kln Post Number: 27 Registered: 02-2002 |
How does the dealership change a battery to prevent catastrophic failures? Do they hook them up in parallel first, or something like that? Paul: What happened to your air-bag circuitry? I'm curious as my SRS light came on last summer after a battery disconnect. I've pulled the fuse as the blinking was driving me nuts. I'm probably going to leave it that way as the air-bags only have 2 years left before they have to be replaced (which will never happen). | ||
| Paul T. Schram (Paulschram) Senior Member Username: Paulschram Post Number: 1243 Registered: 02-2002 |
Kevin: I'm not sure how the Land Rover dealerships do it, but for one thing, they have the ability to reset anything that needs it. Also, I have seen numerous adverts. for devices that allow you to use a 9 volt battery through the lighter to maintain logic current. As for my ABS and SRS, my truck went through a series of alternators shortly before I bought it and as it was being delivered to me (I own a spare alternator!). As a result of repeated operation at low battery voltages, the ECUs were fried to the extent that my ABS ECU is non-communicative to Testbook, Autologic, nor Rovacom! So far, I haven't needed either, and don't really like ABS on an off-road vehicle as it can get squirrelly under some conditions. Low voltage during cranking also causes major problems. Paul | ||
| John Moore (Jmoore) Senior Member Username: Jmoore Post Number: 552 Registered: 10-2002 |
I bought my 99D2 from Robison Service. I told John I was going to replace the stock battery with an Opitma I had used in my former 88RRC. He suggested, to avoid setting off the airbag lights, hooking the new battery up with jumper cables during the install so that the truck would never loose power. | ||
| Bruce Potier (Bruce_flrc) New Member Username: Bruce_flrc Post Number: 14 Registered: 02-2003 |
Geesh, guess I am lucky since I have replaced my battery without keeping the current alive and no problems were encountered. | ||
| Jonathan Hensel (Nanoscale) New Member Username: Nanoscale Post Number: 32 Registered: 03-2003 |
Here here... | ||
| Blue (Bluegill) Senior Member Username: Bluegill Post Number: 2189 Registered: 02-2002 |
I had my hood up in my garage for a week with the battery disconnected. The 96 Disco was just as much of a dog afterwards as before. No faults, codes, or anything else. | ||
| traveltoad (Traveltoad) New Member Username: Traveltoad Post Number: 24 Registered: 11-2002 |
I used to run an autobody repair shop and the lore I've heard is that you can actually blow the air bags when disconnecting/reconnecting the battery. It has to do with getting a power spike or something. I would guess it's the same sort of thing with the ABS too. I've never seen it happen but have talked to people who said that they had. | ||
| Brad Russell (Bradnc) Member Username: Bradnc Post Number: 193 Registered: 03-2002 |
I work at a body shop and i find it rediculous that people would allow that sort of thing to occur. Shouldn't fuses and stuff like that prevent against spikes like that? Maybe when airbags first came out, but not now. We disconnect batteries whenever we're doing a fair amount of work. I don't think you should hesitate about doing so. If somehting happens it's a freak accident. | ||
| traveltoad (Traveltoad) New Member Username: Traveltoad Post Number: 25 Registered: 11-2002 |
I did qualify my post with "...the lore I've heard...". My guess is that a lot of these rumours began when many of these systems were new and the general public had a lower level of understanding. | ||
| Jason T. Barker (Speedminded) Member Username: Speedminded Post Number: 180 Registered: 10-2002 |
I bet most of the problems stated above were caused by improper jumping/boosting of a dead battery and not by just disconnecting the battery. There is nothing wrong with disconnecting the battery unless you re-connect it backwards or ground it. The manuals would not say to disconnect battery (during just about every kind of maintence/repair under the hood or electrical work) if there would be problems by doing so. Yes, when airbags first came out there was alot of problems but what electrical devices don't have problems when they first come out? Also, not just that the airbags were new but they were new to the mechanics working on the cars with them. It not too hard to deploy an airbag if one wrong wire happens to get grounded or something gets crossed up somewhere. |
