E90 320d (auto) doesn’t crank and won’t start

iambmw · 10-04-2020, 05:10 PM

Hi, I have a 2010 320d E90 (auto transmission). Of late, the car is displaying a very weird tendency. It just won’t start on pressing the engine start button while the brake pedal is depressed. There is no cranking sound, dashboard lights turn on, radio plays, even the blower turns on and most importantly the gear selector gets unlocked and I can easily move it to D/N/R as if the engine were on.

However, when I unplug the negative terminal of the battery and leave it disconnected for about 15-20 minutes and fix it back, the engine starts normally. I don’t see an IBS sensor cable on the negative terminal so I guess my car never had one.

This problem has started only very recently and is very erratic and unpredictable. I tried pulling out the CAS relay from the fuse box and plugged it back in but that didn’t help. In fact, nothing works except removing the negative battery terminal and putting it back in after 15-20 minutes. Interestingly, if I fix the terminal back in a shorter time, say 5 minutes, it does nothing. Seems like the battery needs to remain disconnected for some good time for the car to start.

Also, if I keep the battery connected and jump start, it does nothing. If the battery charge were an issue, jumping would have worked, right?

The battery is a non-BMW one and was changed about 2 years ago.

Is it a fault in the starter?

Can anyone please help me understand what has gone wrong? This is becoming a serious problem with the engine denying to fire up every now and then in public places.

Tunafish · 10-04-2020, 06:04 PM

Starter would be prime suspect.. You can test your voltages to starter when issue arise, if you have the 12v suppy and 12v signal when pushing to start, its your starter..

iambmw · 10-04-2020, 07:03 PM

Quote:

Originally Posted by Tunafish

Starter would be prime suspect.. You can test your voltages to starter when issue arise, if you have the 12v suppy and 12v signal when pushing to start, its your starter..

Thanks for your response. I will surely check the volts but curious to understand why would a faulty starter crank the engine after the battery is disconnected for a while and then reconnected. What impact does this have on the voltage?

Tunafish · 10-04-2020, 07:43 PM

Its hard to say for sure and the problem might not be the starter. But testing will confirm..

10-04-2020, 05:10 PM	#1
iambmw Farhan 0 Rep 3 Posts Drives: 320d E90 Join Date: Jan 2020 Location: India iTrader: (0) Garage List 2010 BMW 320d E90 [0.00]	E90 320d (auto) doesn’t crank and won’t start Hi, I have a 2010 320d E90 (auto transmission). Of late, the car is displaying a very weird tendency. It just won’t start on pressing the engine start button while the brake pedal is depressed. There is no cranking sound, dashboard lights turn on, radio plays, even the blower turns on and most importantly the gear selector gets unlocked and I can easily move it to D/N/R as if the engine were on. However, when I unplug the negative terminal of the battery and leave it disconnected for about 15-20 minutes and fix it back, the engine starts normally. I don’t see an IBS sensor cable on the negative terminal so I guess my car never had one. This problem has started only very recently and is very erratic and unpredictable. I tried pulling out the CAS relay from the fuse box and plugged it back in but that didn’t help. In fact, nothing works except removing the negative battery terminal and putting it back in after 15-20 minutes. Interestingly, if I fix the terminal back in a shorter time, say 5 minutes, it does nothing. Seems like the battery needs to remain disconnected for some good time for the car to start. Also, if I keep the battery connected and jump start, it does nothing. If the battery charge were an issue, jumping would have worked, right? The battery is a non-BMW one and was changed about 2 years ago. Is it a fault in the starter? Can anyone please help me understand what has gone wrong? This is becoming a serious problem with the engine denying to fire up every now and then in public places.
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10-04-2020, 06:04 PM	#2
Tunafish Banned 262 Rep 818 Posts Drives: BMW 335i N55 Join Date: Dec 2019 Location: Home iTrader: (0)	Starter would be prime suspect.. You can test your voltages to starter when issue arise, if you have the 12v suppy and 12v signal when pushing to start, its your starter..
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10-04-2020, 07:43 PM	#4
Tunafish Banned 262 Rep 818 Posts Drives: BMW 335i N55 Join Date: Dec 2019 Location: Home iTrader: (0)	Its hard to say for sure and the problem might not be the starter. But testing will confirm..
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