Starting Problem

CSJ · Post by **CSJ** » Sun Jul 05, 2020 8:30 am

I have searched the problems shared by other members and imagine my issue may be a bit unusual. So unusual that it may be difficult to even describe what is happening. My ignorance on how this 2009 3.5 motor operates won't help. I've had no problems starting the car until today when I pressed the start button and the starter didn't engage. What DID HAPPEN is every fan, blower or whatever under the hood on the engine began operating loudly. Furthermore, the only way I could get this to stop was to disconnect the battery. WTF!!! So now the car sits dead in Park and I'm not sure how to even get it to roll into position for tow truck. HELP!!!

tintoverano · Post by **tintoverano** » Sun Jul 05, 2020 9:49 am

did you try reconnecting the battery and see what happens?

CSJ · Post by **CSJ** » Sun Jul 05, 2020 10:28 am

Thank you for that suggestion. Yes, I tried reconnecting battery again to see if issue would clear itself. No luck. Any thoughts on what all is running? Really loud. Must be whatever normally comes on in conjunction with engine start up.

tintoverano · Post by **tintoverano** » Sun Jul 05, 2020 10:46 am

does the starter motor crank?

CSJ · Post by **CSJ** » Sun Jul 05, 2020 11:00 am

No. The starter didn't crank the engine.

tintoverano · Post by **tintoverano** » Sun Jul 05, 2020 11:16 am

perhaps the CAS relay is out, I imagine you don't have a code reader on you

it is located on the fuse box: Kl. 30g

https://e89.zpost.com/forums/showthread.php?t=826566

at the bottom of the left side diagram

also check the fuses

CSJ · Post by **CSJ** » Sun Jul 05, 2020 11:25 am

Thank you! Yes, perhaps this is a relay malfunction. I'll replace and reconnect. I still want to know what IS running. Do the turbos have an electric assist? Intake? Thanks again!

tintoverano · Post by **tintoverano** » Sun Jul 05, 2020 11:28 am

sorry, I got a naturally aspirated one

mcbutler · Post by **mcbutler** » Sun Jul 05, 2020 11:47 am

CSJ wrote: ↑Sun Jul 05, 2020 11:25 am Thank you! Yes, perhaps this is a relay malfunction. I'll replace and reconnect. I still want to know what IS running. Do the turbos have an electric assist? Intake? Thanks again!

No they dont...
Water pump is electric though. A feature of the Z4 is that if you for example drive to the shops on a cold day and decide to wait while the wife goes into the shops. Once you turn off the engine, you press the fan+ button and the centre LED will illuminate, the electric water pump will circulate warm coolant to keep the interior heating going for you.
So, if your water pump is running and your interior fans look for the centre LED, try turning the fan off. If you do have a defect in this system it may have drained your battery to deeply.
I would be charging my battery for a few days and trying again.

CSJ · Post by **CSJ** » Sun Jul 05, 2020 12:21 pm

Thank you. I appreciate all the input and suggestions. It would have to be a very loud water pump. Whatever is running is really loud. The battery is new and has a full charge. Thanks again.

CSJ · Post by **CSJ** » Sun Jul 05, 2020 12:30 pm

If the car can't be started does anyone have a suggestion for getting into neutral so car can be moved? Thanks.

CSJ · Post by **CSJ** » Sun Jul 05, 2020 1:04 pm

mcbutler wrote: ↑Sun Jul 05, 2020 11:47 am
CSJ wrote: ↑Sun Jul 05, 2020 11:25 am Thank you! Yes, perhaps this is a relay malfunction. I'll replace and reconnect. I still want to know what IS running. Do the turbos have an electric assist? Intake? Thanks again!
No they dont...
Water pump is electric though. A feature of the Z4 is that if you for example drive to the shops on a cold day and decide to wait while the wife goes into the shops. Once you turn off the engine, you press the fan+ button and the centre LED will illuminate, the electric water pump will circulate warm coolant to keep the interior heating going for you.
So, if your water pump is running and your interior fans look for the centre LED, try turning the fan off. If you do have a defect in this system it may have drained your battery to deeply.
I would be charging my battery for a few days and trying again.

Thanks again and I'm sure that must be the noise. I've just never heard without the engine running. I'll pull that fuse when located.

CSJ · Post by **CSJ** » Sun Jul 05, 2020 5:16 pm

tintoverano wrote: ↑Sun Jul 05, 2020 11:16 am perhaps the CAS relay is out, I imagine you don't have a code reader on you

it is located on the fuse box: Kl. 30g

https://e89.zpost.com/forums/showthread.php?t=826566

at the bottom of the left side diagram

also check the fuses

So the CAS Relay seems to have been the problem. I removed the relay to inspect, tapped on it in case contacts were stuck, put back in panel, reconnected the battery and the car started right up. After the car ran for awhile I shut it off and proceeded to reinstall the fuse panel. I thought to check the CAS Relay again and it was hot enough to burn my finger. Pretty sure that's not right. I'll buy a new relay and after it's installed I'll check it for heat build up. If it still seems abnormally hot I'll take car to dealer. Thanks again for this forum and for the kind help!!

mcbutler · Post by **mcbutler** » Sun Jul 05, 2020 6:13 pm

CSJ wrote: ↑Sun Jul 05, 2020 5:16 pm
tintoverano wrote: ↑Sun Jul 05, 2020 11:16 am perhaps the CAS relay is out, I imagine you don't have a code reader on you

it is located on the fuse box: Kl. 30g

https://e89.zpost.com/forums/showthread.php?t=826566

at the bottom of the left side diagram

also check the fuses

So the CAS Relay seems to have been the problem. I removed the relay to inspect, tapped on it in case contacts were stuck, put back in panel, reconnected the battery and the car started right up. After the car ran for awhile I shut it off and proceeded to reinstall the fuse panel. I thought to check the CAS Relay again and it was hot enough to burn my finger. Pretty sure that's not right. I'll buy a new relay and after it's installed I'll check it for heat build up. If it still seems abnormally hot I'll take car to dealer. Thanks again for this forum and for the kind help!!

Has your car had the fuse box recall work done??

tintoverano · Post by **tintoverano** » Sun Jul 05, 2020 6:17 pm

CSJ wrote: ↑Sun Jul 05, 2020 5:16 pm
tintoverano wrote: ↑Sun Jul 05, 2020 11:16 am perhaps the CAS relay is out, I imagine you don't have a code reader on you

it is located on the fuse box: Kl. 30g

https://e89.zpost.com/forums/showthread.php?t=826566

at the bottom of the left side diagram

also check the fuses

So the CAS Relay seems to have been the problem. I removed the relay to inspect, tapped on it in case contacts were stuck, put back in panel, reconnected the battery and the car started right up. After the car ran for awhile I shut it off and proceeded to reinstall the fuse panel. I thought to check the CAS Relay again and it was hot enough to burn my finger. Pretty sure that's not right. I'll buy a new relay and after it's installed I'll check it for heat build up. If it still seems abnormally hot I'll take car to dealer. Thanks again for this forum and for the kind help!!

glad to hear

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