roswell

Hello guys and gals, I'm from Bulgaria and new to the forum recently got a 2005 530d 218hp Automatic transmission. I loved the car until it gave me headaches and moments of shame.

I will try to give you as much as info so we could brainstorm together. My problem is the following:

I had a 100Ah Varta S3 Silver battery on the car from the previous owner. When I bought the car, weather was between 15 - 20C. I drove the car with no problems at all for a month.

Now that the weather is colder, drops to -7C, I am not able to start the car in the mornings. I am using my second car (Honda Accord 7th gen diesel which has a Bosch S4 74Ah 700 something CCA) to charge BMWs battery via jump start cables. It takes significant time to charge. Why am I charging it this way? Because when I plug (+) first to Honda then to BMW and then (-) to Honda and then BMW and then I run Honda and leave it running. BMW won't start if I try to start it. Starter will turn but not crank. It will take around 1 hour recharging and with no attempt to start my BMW (above 3C I wait for noon time).

I thought the battery could be dead, I bought a new, same battery. Its specifics are
Capacity: 100Ah
CCA: 830A
I read that there is no need for reprogramming if it is the same battery but only registering. I didn't register it since I was worried if I lose power suddenly ECU could break. I am not sure if this one is registered or reprogrammed either. How can I check if it is registered in INPA? I don't have running DIS .

I thought alternator could be the problem as I read on the forums so decided to check it. If I put my voltmeter on the cables I get 14.30V while idling. If I press on the throttle I get about 15.40V(this is if I measure voltage on the cables on the battery not touching battery terminals!). If I then lift my foot then it goes back to 14.20V 14.30V. This makes me think alternator and voltage regulator is running OK. Am I right? Interesting bit is after driving it 30kms in city if I measure voltage across the battery terminals directly it shows 12.40V while the engine running. If I measure on the cable terminals its 15.30V. Contact areas on battery are not good? I used a toothbrush to clean them with baking soda. So Alternator is working OK but battery is not getting recharged?

LED near the gear lever is going off after sometime. There is a CD changer on the car it's BMW original but there is no CD Magazine where I can put 6 CDs on it. There is a CD inside the CD player and I can hear it still running even if I remove the key. I haven't waited more than 10 minutes to check if it it is still turning the disk after I remove the key.

One other thing to mention is that I don't drive my Honda since I bought my BMW, lol who would The thing is if I try to crank my BMW when I'm using the jumping cables below 3C conditions I get a check engine light on Honda. This forces me to think something is drawing a heck of current when I put the key and try to crank. Maybe starter motor is trying to draw more than battery could supply? Since car is under 3C conditions, I assume it turns on mirror heaters automatically. So mirror heaters, iDrive, dashboard lights, steering wheel up-down motor, seat side tightener motors are working just before I try to crank. All I hear is ticking noise and see a battery with 11.60V.

Is it a good idea to put a AMmeter between + and - in series in order to see what is the cranking current draw. I've got one of those cheap multimeters (10$) so maybe I won't be able to measure cranking current.

Thank you for your interest and inputs in advance. You rock

BenAnd

Hi Roswell

As I hear/read your problems it make mé Think in two directions , first a defect startermotor , had the same problem , with the same symptoms , second it could also be a defect IBS .

Try and feel on the cabel going to the starter when cranking , if it gets warm , it consum to much power and have defect.

IBS you can check by disconecting the blue connector ( wire between + & - pol on the battery ) , if problems go away , you have a defect IBS , can be changed with out coding of the car afterwards.

Regatding the battery , all ways make a new registration when switching it ( Can be done with INPA ) so that the new battery is charged correctly.

Hope this helps you a little

roswell

Since this is a diesel model, do you know location of the starter motor? In all other cars I drove, I had to hold ignition until car started. With BMW it's different now. You just have to turn once and not hold it there and car starts. I like this, it's no different than start/stop button. Maybe a lot of people are doing the way I did in the past and thus having a bad starter causing to draw high current.

If the starter is drawing high current, how much current draw would cause a voltage drop? If my battery's CCA is 830A what I understand from this is battery is able to provide 830A peak. Could a bad starter draw anywhere near that current? I know that a good starter should be around 100 to 200A at max. How much the other things I listed above draw? We shouldn't forget fuel pump, active steering pump and all other pumps right?

BenAnd

Hi

I gess it is located aprox in the same place as on the petrol engine , on the left side in front of the gearbox , should be easy to acses from underneath the car ( car on a lift )

How much power the car draw all together when cranking I can't say ,it World be defferent from car to car depending of the individual car and what extras it got ( nav,klima,logic7,HUD, etc. )

If you get the voltage drop over night , try as mentioned to disconect the IBS .

NB: You have what is called "comfortstart" only press start botton once at the car starts , if you want to "brake off" just release the breakpedal

BimmerFan52

If the starter motor is failing it would not cause the battery to discharge unless you are excessively cranking the engine. From your explanation that is not the case. Also, after charging the battery from the Honda the car starts. At this point I would set aside the starter as a potential cause and concentrate on the battery and alternator.

The function of registering the battery is to reset the age of the battery, the type of battery and the ratings of the battery in the computer. Registration of the battery is designed to extend the life of the battery by charging it properly. Short term, not having the battery registered will have no effect on a new battery’s ability to start the car, unless an FLA type battery (white top battery) is registered and you are using an AGM type battery (black top battery). You mentioned when you increase the engine RPM the alternator output measures 15.4V. An AGM type battery should never be charged with more than 14.7V, and charging at 15.4V can quickly destroy an AGM type battery. Other than overcharging an AGM battery you don’t have to worry about registration until after you sort out the battery discharge problem.

I am confused by your varying voltage measurements at the battery and cables while the engine is running. This is not the best, and certainly not the easiest, place to measure voltage. First, I would insure that the battery cables are securely attached to the battery by gently wiggling cables. If tight then leave them alone. Both cables have special functions and are sensitive to rough treatment and very expensive so you don’t want to do any strong pulling or prying on them. The best place to measure voltage is under the hood at the jump terminal and ground terminal which you should also use to jump the car if you are not.

Once the car is started you need to drive it for a good half hour to an hour on the highway. Then measure the voltage under the hood while the engine is running. It should read 14.2-14.5V at idle. Then turn the engine off and turn the headlights on for 2 minutes to remove the surface voltage from the battery (which will give you a falsely higher reading). Then measure the battery voltage with the engine off. If the voltage on the new battery is not 12.5-12.6V then all signs would point to your alternator not charging the battery.

If the battery does measure 12.6V then the next step is to find out how quickly the battery is discharging. I would measure the battery voltage again multiple times over the day several hours apart to document the discharge of the battery. You must then determine what is discharging the battery.

One of the functions of the IBS is to measure current usage while the car is asleep and wake up the DME to allow it to turn off loads. This wakeup event is designed to happen only once. However, at times the IBS can malfunction and repeatedly wake up the DME. The current required to run the DME is significant and can quickly drain the battery. Other common sources of parasitic current drain include aftermarket items such as radar detectors that are incorrectly attached directly to an always hot circuit and will drain the battery while the car is at rest.

You may also want to consider the purchase of a plug-in voltmeter, which you can use to measure the voltage before starting, watch the alternator current ramp up in the first 15 seconds after starting and constantly monitor voltage during the drive. When my alternator voltage regulator failed it would be fine sometimes and then be erratic. I used a unit like this one to actually see when it went bad.

roswell

Thank you for your very thorough input. I personally think, this world needs more technically oriented people than most of the other professions. One thing I noticed this morning is that there was no sign of ice/snow on my car other than roof of the car. It was snowy last night. I returned home at 20:00 and left the car over night at 6:00 a.m. today, all other were covered in the snow!!!!! Like somebody used it and parked it where I left :O

Ok, I think I really wrote my post in a very complicated way.

The fact that car is running when jumped makes me think starter is not bad. I should probably take pictures of back of my car in order to diagnose this issue. Back of the car is not really in good condition when I compare the battery compartment of my car and the ones in the internet.

I don't think this battery is AGM. I didn't find any documentation showing that it's AGM.

A running 2.2lt 140hp Honda diesel should be able to run 3.0lt BMW 218hp. at first attempt? I can't always get a helper so I'm on my own.

My next plan of action is disconnect IBS and while IBS is disconnected jump start the car from the jump start under the bonnet.

I bought a voltage regulator. It's a Valeo but haven't had it fit yet. 100 euros to just it get replaced seems to be a lil bit on high side as this can be done without removing alternator.

I was avoiding BMW authorized dealer service but I want to travel around 2000km so I don't want to leave the things to luck and least I'll know what to watch out I guess.

BimmerFan52

Disconnecting the IBS will not make the car any easier to jump. The problem with jumping these relatively new cars is all of the computers that must be powered before you even crank the engine.

I am not familiar with the location of the alternator on your engine type. On mine there is no way the voltage regulator could be replace while the alternator is in the car. The space is just way too tight.

Make sure you know the alternator is not charging the battery before you go to the trouble of replacing the voltage regulator. Otherwise the battery may be good and the alternator may be good but something is discharging the battery. In that case if you replace the voltage regulator it will not solve your problem.

roswell

I measured the battery last night without cranking and it showed exactly 11.87V. This morning without even getting on the car measure 11.87V again. This should eliminate the probability of having a parasitic power drain on the car right?

Just so you know that I don't use the key to open the trunk. I unlock it via remote so car is awoken and the light next to shift lever is then illuminated.

Can it be that IBS sensor detected that my old battery cannot be charged anymore and it is not letting alternator charge the battery?

So since I have not registered the new battery could it be IBS simply blocking alternator from recharging the battery by not completing the circuit on the negative terminal?

Thanks for your input. I actually enjoy diagnosing this as I gain experience and perhaps life saving knowledge?

roswell

Tried to jump start the car with no success . I didn't clean the terminals on my 2nd car battery though. They started to corrode. My cables may be gone bad as well I don't know. At least I managed to register the new battery in INPA.

It turns the engine but not enough compression to ignite I'll give it another try after I clean my Honda's battery terminal.

I've got a question, should the aiding car (which is in running condition) be powerful as jumped car in order to be able start the engine at first try?

Shouldn't a running car be able to provide enough juice given that it's another diesel which also powerful?

BimmerFan52

It is possible that not seeing a drop means that you have no parasitic current drain.

You don't need to go to the trunk at all except to check the battery connections once. Do all of your jumping and voltage measurements under the hood.

But I am still unclear. Is the battery getting to a full charge after you drive it? If you drive it an hour and the brand new battery doesn't measure 12.5V+ then either your alternator is not charging it, or the battery is bad and cannot be charged.

The IBS cannot prevent the alternator from charging the battery. It only takes measurements, stores and send info to the DME and can wake up the DME if it sees that net current to the battery is negative.