Bad alternator or batteries?

[titanle]

I had the X6 in the shop to do an adaptation reset on the engine and transmission in hopes of fixing the jolt I get when coasting to a stop. They came back and said for some reason around the 20km mark where it occurs, the engine switches on for a split second.

The adaptation did not solve the issue and they're saying it could be the engine, transmission, dme or the mechatronics.

Now since I got the vehicle back, I've been getting multiple errors such as restraint system, chassis stabilization, increased battery discharge and the red airbag light on the dash.

Could this be related to what they did or is this more likely a battery or alternator issue?

[Sophisticated Redneck]

I had same jolt on mine as well as other issues with transmission. Replacing the solenoids made it drivable again, that was 50k miles ago. Solenoid's run 300-500 for a set depending on if you have a 6 speed or 8 speed. Plus another couple hundred for new oil and pan/filter and expect 400-500 in labor.

When was the last time the transmission fluid was changed?

As for electric issues, first get your battery tested but it sounds like a short or possible bad ground strap. There are two major grounding points along with dozen more smaller locations located throughout the truck, start with the major ground straps first located on driver's side by steering rack (have to go under truck to see) and second that connects in rear by muffler.

[Serf27]

A faulty or failing alternator will cause a mess of errors similar to the ones you’re experiencing.

[titanle]

Originally Posted by Sophisticated Redneck

I had same jolt on mine as well as other issues with transmission. Replacing the solenoids made it drivable again, that was 50k miles ago. Solenoid's run 300-500 for a set depending on if you have a 6 speed or 8 speed. Plus another couple hundred for new oil and pan/filter and expect 400-500 in labor.

When was the last time the transmission fluid was changed?

As for electric issues, first get your battery tested but it sounds like a short or possible bad ground strap. There are two major grounding points along with dozen more smaller locations located throughout the truck, start with the major ground straps first located on driver's side by steering rack (have to go under truck to see) and second that connects in rear by muffler.

I'm at 70,000 kilometres and have the 8 speed transmission. I have never had the fluid changed out.

I'm going to take the batteries to have them tested today. These Canadian tire agm batteries aren't that good, I should have done my research before buying. When you say bad ground strap, do you mean a possible loose connection or a broken wire somewhere?

All of the new error messages have disappeared now, the only one remaining is the passenger restrain system error and even that comes and goes, before it was constant.

[hyeprofile]

I also put on a Canadian Tire AGM battery 2 years ago, and it's held up well, but I do get the "increased battery discharge" warning quite a bit in the winter, even after doing the new battery procedure in ISTA+.

But what's crazy is that 3 weeks ago I was on a camping trip for the long weekend so I hadn't started the car for 3 or 4 days while camping, but on the last day I started it 3 times without driving too much in between, and after the 3rd start I started the long drive back home and suddenly all the ECUs started failing one after the other (error messages posted every 5 to 10 seconds, hinting that the ECU is shutting down), then the main screen shut down, then the engine went into VERY LIMP mode and then everything shut down and the car stopped (in the middle of nowhere, in mosquito hell). I immediately suspected a short but couldn't find anything obvious. Was a bitch to get it towed back home (thank god I have a Canadian Tire Mastercard with free roadside assistance that includes up to 250km towing!!!) cause I needed to crawl under the car to screw the transmission into neutral so we could pull it onto the flatbed. It's been 3 weeks and I still can't get the car to start. Troubleshooting is getting me nowhere...

[Sophisticated Redneck]

Originally Posted by titanle

I'm at 70,000 kilometres and have the 8 speed transmission. I have never had the fluid changed out.

I'm going to take the batteries to have them tested today. These Canadian tire agm batteries aren't that good, I should have done my research before buying. When you say bad ground strap, do you mean a possible loose connection or a broken wire somewhere?

All of the new error messages have disappeared now, the only one remaining is the passenger restrain system error and even that comes and goes, before it was constant.

Here is a link to a thread that will teach you all about the ground strap, it's location, and how to replace. May not be your issue but good to check out anyway as this single cable is notorious for breaking/corroded

https://www.xbimmers.com/forums/show....php?t=1632755

[Sophisticated Redneck]

Originally Posted by hyeprofile

I also put on a Canadian Tire AGM battery 2 years ago, and it's held up well, but I do get the "increased battery discharge" warning quite a bit in the winter, even after doing the new battery procedure in ISTA+.

But what's crazy is that 3 weeks ago I was on a camping trip for the long weekend so I hadn't started the car for 3 or 4 days while camping, but on the last day I started it 3 times without driving too much in between, and after the 3rd start I started the long drive back home and suddenly all the ECUs started failing one after the other (error messages posted every 5 to 10 seconds, hinting that the ECU is shutting down), then the main screen shut down, then the engine went into VERY LIMP mode and then everything shut down and the car stopped (in the middle of nowhere, in mosquito hell). I immediately suspected a short but couldn't find anything obvious. Was a bitch to get it towed back home (thank god I have a Canadian Tire Mastercard with free roadside assistance that includes up to 250km towing!!!) cause I needed to crawl under the car to screw the transmission into neutral so we could pull it onto the flatbed. It's been 3 weeks and I still can't get the car to start. Troubleshooting is getting me nowhere...

You should check your ground strap too (Assuming you already tested battery), see link I just posted above.

[titanle]

In terms of testing the battery, previously I disconnected the negative terminal from each battery and connected the Noco smart charger to each battery separately. Both charged up to full with the green light in less than 5 minutes.

Is that an accurate way of testing the battery? Should I remove both the negative and positive terminal and then put each one on charge?

I haven't had time to tackle the ground strap issue at this time.

[Sophisticated Redneck]

Originally Posted by titanle

In terms of testing the battery, previously I disconnected the negative terminal from each battery and connected the Noco smart charger to each battery separately. Both charged up to full with the green light in less than 5 minutes.

Is that an accurate way of testing the battery? Should I remove both the negative and positive terminal and then put each one on charge?

I haven't had time to tackle the ground strap issue at this time.

No that doesn't really test the battery, best you take it to a local Autozone, Napa, or Orileys and have them test it for you as they will do it for free . The battery tester puts various high-amperage loads on the battery and measures the voltage drop under these loads over time.

[titanle]

Will do. I've already had one of the two new batteries replaced under warranty since it didn't hold charge. I wouldn't be surprised if one of them is dying now.

I think it's possible the dealership left the car on or something while doing their diagnostics and allowed the battery to drain. I had a bunch of errors show up the first day and now even the restraint system error is gone. The red light with a seatbelt is on but that's about it.

[Thecastle]

Make sure the battery is the right capacity for your vehicle. I had similar problems on my 335d as the previous owner had installed a 60ah flooded instead of a 90ah agm. Lots of increased battery discharge and over time things like the radio would get shit off while driving. All fixed when I researched and replaced the battery with one of the correct capacity.

A lot of battery places don’t check to see if the correct battery is installed. They just swap same for same or what they have in stock..... bmw does sell a 105ah battery for our cars.

Also with the e70 x5s. I’ve had 3 alternator die on average Every 40k miles. 2x on a 2008 4.8i one at 41k, and second at 87k. Once on my 2011 x5m at 43k while on a trip. Had to go retrieve it weeks later.....

The v8s are known for eating batteries on the e70s and I weekly trickle charge mine to keep it happy. https://www.roadandtrack.com/car-cul...ns-bmw-n63-v8/