[loganmecham]

I just replaced my water pump a month ago and it has already stopped working.
I checked the fuse (not blown)
I cannot figure out why it has stopped working again and I need help fast as I am out of town and 5 hours from home.
I tried to reset/bleed the pump (car on heat up fan down gas pedal 10 secs), and the pump did not kick on. Is it a problem with the cars computer?
Any help would be greatly appreciated

[loganmecham]

More background information on the many problems my car has been giving me lately.
In cold mornings it doesn’t want to start and I had to jump it three times this morning to keep it running. Even when I did get it running I would have to turn it on and off repeatedly because the transmission was locked in park and giving me a transmission malfunction code along with a AWD system error code. It only seems to do this every once in a while on especially cold mornings. I left it at an airport parking lot for 10 days and it started right up with no problems and I drove home but the next morning my wife couldn’t get it out of park and it died after 2 minutes. I don’t want to give up on this car but it’s pushing me dangerously close to getting rid of it. Thanks again for any feedback

[SixSix]

I have a buddy with a 2006 E90 335, his car did pretty much the same stuff however I didn't test the water pump to cycle it and see if it would work. His ended up throwing a stupid amount of codes and ran like sht... I diagnosed it as a voltage regulator, swapped it out for him and it fixed the issue. These cars can freak out if DME voltage isn't stable. This sounds very similar to his issue so I would recommend checking your battery voltage first, then dealing with the voltage regulator. If I remember correctly the voltage regulator is relatively cheap so maybe start with that or take a multimeter to the alternator output and see what voltage it's making when the engine is running. Let me know how it goes.

[loganmecham]

Originally Posted by SixSix

I have a buddy with a 2006 E90 335, his car did pretty much the same stuff however I didn't test the water pump to cycle it and see if it would work. His ended up throwing a stupid amount of codes and ran like sht... I diagnosed it as a voltage regulator, swapped it out for him and it fixed the issue. These cars can freak out if DME voltage isn't stable. This sounds very similar to his issue so I would recommend checking your battery voltage first, then dealing with the voltage regulator. If I remember correctly the voltage regulator is relatively cheap so maybe start with that or take a multimeter to the alternator output and see what voltage it's making when the engine is running. Let me know how it goes.

Thanks for the suggestion that sounds like that might be my problem. I have a 10 hour drive tomorrow to get my car home and then I’ll test that ASAP and update this thread.

[SixSix]

I'm sure you've figured this, but don't overheat your car, you'll end up having much bigger issues than just an alternator issue. Just limp it back and let it cool off if need be

[loganmecham]

Originally Posted by SixSix

I have a buddy with a 2006 E90 335, his car did pretty much the same stuff however I didn't test the water pump to cycle it and see if it would work. His ended up throwing a stupid amount of codes and ran like sht... I diagnosed it as a voltage regulator, swapped it out for him and it fixed the issue. These cars can freak out if DME voltage isn't stable. This sounds very similar to his issue so I would recommend checking your battery voltage first, then dealing with the voltage regulator. If I remember correctly the voltage regulator is relatively cheap so maybe start with that or take a multimeter to the alternator output and see what voltage it's making when the engine is running. Let me know how it goes.

Just got done replacing the alternator. I took my battery in to get it tested and it is good. Brand new alternator, new good battery, but if I hook the multimeter up to the battery terminals it visibly is losing volts still. It dropped 12.4 to 12.25 in about 30 seconds. So there is still clearly a draw on my battery when there shouldn’t be.
Also my water pump still isn’t working. I drove it around and tested it out and the engine and coolant got hot but the heater in the cab never warmed up and when I tested the pump it still wouldn’t kick on. I have it hooked up to a battery charger but I’m not sure what to do next. I checked the water pump fuse again and it’s still good. Anybody have any ideas? I hope I don’t have to replace the water pump again I just replaced it a month ago

[2Ringfan]

How old is your battery? Does the voltage keep dropping or level ar 12.25? What voltage do you get under the hood?
You should see high 13 low 14 at battery with engine running.
All of that said, your trip from the airport may not have been enough to recharge. maybe.
Or you may have a parasitic draw. That's another test.
Who programmed the battery to the car?
Some of your problems sound like low voltage but pump may/may not be related.

[loganmecham]

Originally Posted by Phemisg

How old is your battery? Does the voltage keep dropping or level ar 12.25? What voltage do you get under the hood?
You should see high 13 low 14 at battery with engine running.
All of that said, your trip from the airport may not have been enough to recharge. maybe.
Or you may have a parasitic draw. That's another test.
Who programmed the battery to the car?
Some of your problems sound like low voltage but pump may/may not be related.

I replaced my own battery three months ago. I programmed it myself and I told the IBS there was a new battery when I replaced it. I haven’t tested the voltage while the car was running so I will go do that and update. I left a battery charger on my car for 16 hours and pulled it off when it read 12.5 dropping to 12.25 so that seemed to me like the battery had a parasitic draw that wasn’t letting it charge completely. Hopefully this huge expensive battery just takes a long time to get up to the proper voltage level because I really don’t want to replace my 3 month old water pump again.
Will test battery while running and update.

[ctuna]

When the car wakes up there will be voltage drop on the battery as
the car starts drawing about .5 amps immediately . This will cause the battery
voltage to drop some depending on the state of the battery and on a
weak battery it will have the biggest effect. To get a voltage reading with
the least amount of draw on the battery lock the car.

If you run the car without the water pump working you are looking at an Engine replacement.
You need BMW capable diagnostics to work on these cars.
The purge procedures exercises the water pump and is and indirect way of seeing if it
works.

[loganmecham]

Originally Posted by ctuna

When the car wakes up there will be voltage drop on the battery as
the car starts drawing about .5 amps immediately . This will cause the battery
voltage to drop some depending on the state of the battery and on a
weak battery it will have the biggest effect. To get a voltage reading with
the least amount of draw on the battery lock the car.

If you run the car without the water pump working you are looking at an Engine replacement.
You need BMW capable diagnostics to work on these cars.
The purge procedures exercises the water pump and is and indirect way of seeing if it
works.

Ive used bmw capable diagnostic tools for every repair so far. I’ve run the water pump purge cycle multiple times and the water pump refuses to kick on. I let the car cool every time it overheated before starting it and only drove as far as absolutely necessary when the water pump stopped working.
I just don’t understand why my water pump would go bad with less than 5k miles and less than 3 months of wear.
I tested the battery and while off it sits at 12.25 volts and while running it sits at 14.10 volts. I think the only logical thing here is that my pump died. oh well I will just have to replace it again I guess.

[loganmecham]

Originally Posted by Phemisg

How old is your battery? Does the voltage keep dropping or level ar 12.25? What voltage do you get under the hood?
You should see high 13 low 14 at battery with engine running.
All of that said, your trip from the airport may not have been enough to recharge. maybe.
Or you may have a parasitic draw. That's another test.
Who programmed the battery to the car?
Some of your problems sound like low voltage but pump may/may not be related.

I checked again this morning with the car off and not awake and the voltage read 12.25V and stayed there. I didn’t notice any major parasitic draw on the battery this time with the car completely asleep. I started it up and the voltage jumped up to 14.10 and sat there pretty comfortably from then on so I don’t think battery/IBS/alternator is my problem.
All signs point to a dead pump at this point.

[SixSix]

Is it still doing the AWD fails and and having more issues than just the water pump? What are the codes that the car is showing?

[2Ringfan]

Originally Posted by loganmecham

I checked again this morning with the car off and not awake and the voltage read 12.25V and stayed there. I didn’t notice any major parasitic draw on the battery this time with the car completely asleep. I started it up and the voltage jumped up to 14.10 and sat there pretty comfortably from then on so I don’t think battery/IBS/alternator is my problem.
All signs point to a dead pump at this point.

A real parasitic draw will take it down to zero. Your numbers look fine if the battery holds steady.
As to the pump, is it possible it is not getting a signal to start? I'm not familiar with the system, but there has to be some sensor that reads temp and controls the pump. Try searching for that.
My car was not properly coded to the last battery. Trying to determine the right number is not always clear. In my case, the battery seldom got over 12 when shut off. Cooked the battery. New battery and coding seems to work. you may be OK. Or not.

[gbalthrop]

Originally Posted by loganmecham

I just replaced my water pump a month ago and it has already stopped working... I checked the fuse (not blown) [WHICH fuse? On your 2006 model, F02 is Control & F09 is main power, BOTH in E-box under hood]. I cannot figure out why it has stopped working again [What Brand & Part# was the replacement? What Fault Codes were read BEFORE replacement? What Voltage Tests were made, where & under what conditions before replacement?]

Originally Posted by loganmecham

Just got done replacing the alternator. I took my battery in to get it tested and it is good. Brand new alternator, new good battery, but if I hook the multimeter up to the battery terminals it visibly is losing volts still. It dropped 12.4 to 12.25 in about 30 seconds. So there is still clearly a draw on my battery when there shouldn’t be. [SURFACE CHARGE is a concept you might want to acquire. Use a DMM to test system voltage with engine running (test at Jumpstart Terminals under hood). With engine running, meter should read ~ 14V. Immediately after engine OFF, meter should read ~ 12.9V. That Voltage should decrease to ~ 12.5V in 30 minutes. Once that "Surface Charge" has dissipated, the voltage should remain steady. That voltage decrease has NOTHING to do with parasitic draw by the vehicle. The same would be measured at the battery terminals of a free-standing battery after removing battery charger.]...Also my water pump still isn’t working...

Originally Posted by loganmecham

I checked again this morning with the car off and not awake and the voltage read 12.25V and stayed there. I didn’t notice any major parasitic draw on the battery this time with the car completely asleep. I started it up and the voltage jumped up to 14.10 and sat there pretty comfortably from then on so I don’t think battery/IBS/alternator is my problem. All signs point to a dead pump at this point.

Do you have any Diagnostic Software (INPA/ISTA) or Tool that can "Activate" the Coolant Pump, OR read Pump Speed Parameter/ Live Data? If you confirm that the Pump is NOT running at any speed, then check BOTH F02 and F09 in the E-box. If BOTH have ~ 12V+ with Ignition ON (F09 should be Battery Power, KL30), then time to drop the front splash shield and test at the Pump Connector.

Let me know the results up to that point, and I'll provide wiring diagrams and Connector View with test suggestions.

George

[mainbearing]

+1 check the connector. Which brand of pump did you get? New and not reman?

My factory pump, when commanded to 100%, would not turn above something like 85%. It had not set any code then, but I went ahead and replace the thermostat and pump (Pierburg). And that got rid of the jet engine sound.

The initial voltage drop sounds normal, if it creeps back up to 12.4-12.5v later.

[2Ringfan]

Update?