E60 M5 Charging Fault and High Rate of Battery Discharge
Discussion
I know there are lots of postings on this topic, however, I thought I should share this as it’s different. After searching the postings on the forum, I did not find anyone who had both the Charging Fault and High Rate of Battery Discharge/Increased Battery Discharge errors regularly, within a short period of time. Other members had one or the other error and not both: this is possible, though.
Mine is an 05 model with 65k miles and based in the UK. My situation was that the Charging Fault error would appear on the dashboard a few minutes after I started car, when the engine was cold. I would drive the car for about 10,20,30 mnutes (irrespective of specific timings), stop the car, and when I tried restarting it, the High Rate of Battery Discharge or Increased Battery Discharge error would appear on the dashboard. When this error appeared, the car would not start and had to be jump-started.
BMW dealership wanted to spend hours/Days diagnosing the reason for both errors—no, sir! The postings on this forum helped in determining the possible Root Cause and the elminination process: Battery, Alternator, Alternator Regulator, TCU (also known as Charging Electronics for Handsfree), or the IBS cable.
The posts by other members mostly advised that if one got only the Charging Fault error, the cause was likely due to a faulty Battery, Alternator Votage Regulator or the Alternator itself. If one got only the High Rate of Battery Discharge error, it was mostly the TCU or the IBS cable fault.
I had my alternator reading taken and it was low. Under seller warranty, the Voltage Regulator in the Alternator was replaced (this is more cost effective than replacing the Alternator). After that, both errors did not re-appear and I‘ve since driven over a thousand miles. I did not have to replace the battery, TCU or the IBS cable.
I would suggest that if both errors appear simultaneously on a regular basis, and you’ve done the basic standard checks (battery/alternator tests), you could consider replacing the Voltage Regulator first.
Mine is an 05 model with 65k miles and based in the UK. My situation was that the Charging Fault error would appear on the dashboard a few minutes after I started car, when the engine was cold. I would drive the car for about 10,20,30 mnutes (irrespective of specific timings), stop the car, and when I tried restarting it, the High Rate of Battery Discharge or Increased Battery Discharge error would appear on the dashboard. When this error appeared, the car would not start and had to be jump-started.
BMW dealership wanted to spend hours/Days diagnosing the reason for both errors—no, sir! The postings on this forum helped in determining the possible Root Cause and the elminination process: Battery, Alternator, Alternator Regulator, TCU (also known as Charging Electronics for Handsfree), or the IBS cable.
The posts by other members mostly advised that if one got only the Charging Fault error, the cause was likely due to a faulty Battery, Alternator Votage Regulator or the Alternator itself. If one got only the High Rate of Battery Discharge error, it was mostly the TCU or the IBS cable fault.
I had my alternator reading taken and it was low. Under seller warranty, the Voltage Regulator in the Alternator was replaced (this is more cost effective than replacing the Alternator). After that, both errors did not re-appear and I‘ve since driven over a thousand miles. I did not have to replace the battery, TCU or the IBS cable.
I would suggest that if both errors appear simultaneously on a regular basis, and you’ve done the basic standard checks (battery/alternator tests), you could consider replacing the Voltage Regulator first.
Mine did this a long while after a new battery not being coded to the car properly.... replacing the cable as said above solved the problem....
then the bluetooth mule broke at a similar time.
That problem was down to the mule being faulty - the handsfree gradually stopped working.
Good news is a used one from a breakers is 125 pounds. A new one from BMW is 400 plus but should be coded to your car.
Internet will give you too many answers but this is what happened to me and many many painful months trying to locate it.
then the bluetooth mule broke at a similar time.
That problem was down to the mule being faulty - the handsfree gradually stopped working.
Good news is a used one from a breakers is 125 pounds. A new one from BMW is 400 plus but should be coded to your car.
Internet will give you too many answers but this is what happened to me and many many painful months trying to locate it.
Yours is yet another variant of the problem,it is a painful elimination process! Good you didn't need to replace the Alternator Voltage Regulator as well. You're right, many scenarios and different answers on the internet. Not a bad idea to have one TCU handy, I got one from ebay for £110---just in case. Not a good idea to buy aftermarket electronics parts, a used one is indeed fine compared to the silly price BMW want for it. BMW told me they don't sell the single IBS cable anymore, they now sell a set of three cables for £200. Did you buy the three set of cables or did you buy a used one?
Quarry motors are local to me so anything I buy from there gets exchanged if it doesnt work, plus they fit and fix cars over the road at their servicing place.
I forget how much the cable was but it did fix the issue - rather than replacing the alternator and other expensive none correct answers. Sytner sheffield are mainly clueless.
I forget how much the cable was but it did fix the issue - rather than replacing the alternator and other expensive none correct answers. Sytner sheffield are mainly clueless.
Lol---funny how it had to be Sytner! They told me I needed a new Alternator---£700!
Mine was definitely the Voltage Regulator inside the Alternator. Result of the voltage/alternator test was jumping high/low/ then jump start. It's good to see different owners posting different fixes. As long as people do the usual tests/checks first (alternator, battery test, etc, they can narrow the problem down to what it is.
For other owners who may need the info: Original Voltage Regulator from BMW is £110 (12318510092). Original IBS cable from BMW (a set of three) is £196(61127616200, 61129123572 and 12517615476). TCU/Charging Electronics for Handsfree is £560(84109226711) but £120-£150 used on ebay-----different types for the same M5 models so, easy to remove the faulty one to check that the part number matches the one you buy.
Mine was definitely the Voltage Regulator inside the Alternator. Result of the voltage/alternator test was jumping high/low/ then jump start. It's good to see different owners posting different fixes. As long as people do the usual tests/checks first (alternator, battery test, etc, they can narrow the problem down to what it is.
For other owners who may need the info: Original Voltage Regulator from BMW is £110 (12318510092). Original IBS cable from BMW (a set of three) is £196(61127616200, 61129123572 and 12517615476). TCU/Charging Electronics for Handsfree is £560(84109226711) but £120-£150 used on ebay-----different types for the same M5 models so, easy to remove the faulty one to check that the part number matches the one you buy.
PrettyBeast said:
…………..High Rate of Battery Discharge………...
Thanks for sharing this experience, inredibly useful in diagnosing the electronic mysteries and turning them into solutions…..I had a somewhat similar problem, not as complex and a far simpler issue as it turned out……
I had the High Rate of Battery Discharge warning come up.
But only after the battery was on a C-TEK Battery tender.
Solved by another forum member suggesting the car was "seeing" a discharge when the C-TEK was disconnected…!!
That was all it was….
Have over 20 years experience of dealing with BMW Technical Service and they certainly appear to be struggling these days.
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