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Discussion Starter #1
Here waths happening (sometimes):

It only happens with a hot engine, from time to time:

The temperature meter goes in red, the handbrake led turns yellow, the car cranks but won't start.
My first idea was a bad temperature sensor, so I replaced the temperature sensor, tought it was ok but a couple of days ago, on a hot summerday it happend again. Sometimes it helps when I turn the key over and over again, suddenly its all normal, sometimes I have to let cool down a couple of hours. The cooling system is just worling fine, engine temp. is ok.
I read a simmilar case on the net and the sollution there was a bad rlay (the bleu one next to the ECU) I ckecked that one out but works just fine!

I'm guessing the car has an electrical problem or a bad sensor, connector, relay... but I could really use some hints here, its strange it only comes with a hot engine. Deu to that I think I can ignore any brake/abs problem?

When I read the OBD I only get a error code from the swirl flaps, they are gone be rmoved in the summer hollidays.


This is a real sticky problem for me, so any suggestions wil be welcome!
THX!
 

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Get a better code reader, Creator C110 or C310.

Plus if the blue relay is suspect, just replace it, it's only a few Euros.
 

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Discussion Starter #5
No exrta codes were found.
I'm realy going for an electric problem or sensor, maby the crank sensor?

When testing everything I noticed that my multileter gives 18V with the engine off and 21V with a running engine, I presume this would be 12V?! Could this cause my problem? And if yes, what part do I have to replace?

THX
 

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Discussion Starter #6
O, the relays where replaced, bleu one is working fine, the one behind the glovebox that is going to the fuel pump also, ist this ons that don't get power when the problem ocures, the relay is switched with an other but the problem stays... from time to time....
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 100K miles NOKIAN WR G3 20K miles
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No exrta codes were found.
I'm realy going for an electric problem or sensor, maby the crank sensor?

When testing everything I noticed that my multileter gives 18V with the engine off and 21V with a running engine, I presume this would be 12V?! Could this cause my problem? And if yes, what part do I have to replace?

THX
Not likely the cause, but definitely a problem! 21 VDC will cook the battery in short order.
 

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Discussion Starter #8
any idea what could be the problem then? I'm going to replace the regulator in the alternator for the 21DC problem. I think I have to remove the alternator completely, the steering pump is above and that is probebly have to come out first... hell of a job:(
 

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Discussion Starter #10
THanks for the tip joylove!
just put in on a new 9V battery and its shows 13V, put it on my wifes car and...18V.

I'm happy that I don't have to remove te alternator, but in the mean time I'm still stuck on the fail/safe mode! Tryed allmost everything and no error code, when the problem ocures I can't make a connection on the OBD2...

Any tips are more than welcome on this one! In two we would like to a trip with the car and don't want to get a fail mode when I'm 1000 km from home!!!
 
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