Page 1 of 1

Intermittent No Start (No Crank, No Click) 2004 BMW Z4

Posted: Wed Oct 18, 2017 11:02 pm
by mirccr
2004 BMW Z4 2.5i with 105k miles

Intermittent no crank, no click, lights bright (no dimming), no start issue.
Sometimes it works after a few tries, sometimes it doesn't work for a whole day.

Recent events before the issues:
- Replaced factory amplifier with OEM amplifier.
- Attempted to replace factory head unit with aftermarket head unit, used harness adapter, no wire cutting, just plugging. Disconnected battery negative terminal during the attempt. I was missing the antenna adapter so ended up putting the factory radio back before reconnecting battery.
- Passenger side mirror assembly is broken, controls work, the head is held together with duct tape.

A week after the amplifier work and a couple days after touching the radio:
Day1:
I idle the car at a park for about half an hour one night. I stop the engine and after a while I turn the key, first occurrence of no start. I retry immediately and it works. Works a few more times during the same night. I move on with a shrug.

Day2:
No start in the morning. Try again a few times and it doesn't work. I check the voltage with multi-meter, reads 12.5 to 12.6. I call AAA, while I am on the phone (about 5 minutes after the first attempt) I try it and it works. 8 hours later starts fine and I drive home. Starts a few more times with no problems. I drive to a nearby grocery store and after 20 minutes it doesn't work for a few tries. I wait about a couple minutes and retry, it works. Keeps working during the same night multiple times in variable intervals.

Day3:
No start in the morning. Try again many times during the day and it doesn't work.

Day4:
No start all day. I order a new aftermarket starter on Amazon. Bosch SR0448N New Starter

Day5:
No start in the morning. AAA tows it to mechanic. I want to replace the starter no matter what so the mechanic (I'm not sure if he ran any diagnostics first) replaces the starter and tells me that "it was the starter, it works now". It works many times on site, I drive off. I get the windows and seals aligned at a nearby shop for a leak issue. I drive home. Since I had acquired the correct antenna adapter, I get on replacing the radio. Disconnect negative battery terminal, remove factory radio, plug in the aftermarket radio (using two way harness and antenna adapters). Before putting it in the housing, connect battery and try the radio, doesn't work (key in position 2, all lights work.) I turn the key again to start the car, doesn't start on first attempt. I try again immediately and the car starts. The radio still doesn't work. I stop the engine, disconnect battery negative again, disconnect the aftermarket radio and put the factory radio back. Connect battery, key in pos 2, radio and lights work. I turn the key but car doesn't start. try a few more times, no start. Try again later at night, no start.

Day6:
No try in the morning (I should have). Called AAA for towing, a couple hours later guy tries on parking gear no start. Tries in neutral no start. Tries again in neutral it starts. I drive to a different and more reputable mechanic for diagnosis. No repro the whole day. Car stays there overnight.

Day7:
Mechanic can't repro the issue all day. The mechanic mentions codes from EWS and oil sensor. They are one of the most reputable shops in the area (they only do bmw's) and they don't even have a gut feeling without a repro.

I have only one key.

Other things that may or may not be relevant:
- Key used to close windows from outside the car when I plug it in (not remote), it does not anymore. I did the key reset with "press such and such buttons 3 times" procedure.
- I noticed once or twice that my windows were dropped a couple inches when the no start issues were happening.
- For a couple months (or a few) I see yellow oil warning come up in the dashboard, then go away after a while. I did oil change very recently.

I did a lot of reading and I udnerstand it could be many things, but I'm hoping that the way my issue has progressed and the details can give someone a gut feeling.

Thanks in advance.

Intermittent No Start (No Crank, No Click) 2004 BMW Z4

Posted: Wed Oct 18, 2017 11:10 pm
by Ducklakeview
Ignition switch. £5 part from a breaker, very common.

The switch itself, NOT the key part. Comes off easily and is a 10 min job.

Yellow oil warning lamp means low level if it appears as you turn off the engine, usually accompanied by the warning bong.

Mike

Intermittent No Start (No Crank, No Click) 2004 BMW Z4

Posted: Wed Oct 18, 2017 11:18 pm
by ph001
Yep, ignition switch. Come up lots of times before.

Intermittent No Start (No Crank, No Click) 2004 BMW Z4

Posted: Thu Oct 19, 2017 2:17 am
by mirccr
Thank you very much for the fast replies. I just picked up the car from the mechanic and it works fine. Here are their notes:

-Found EWS fault 27A4 logged 2 times, not currently present. This would cause a no crank situation.
-Checked batter and connections OK
-Fault for oil level sensor logged. Wiring goes through ignition switch and possibility of shorting out ignition switch

So I understand that the seldom yellow oil warning after startup can be explained by the sensor fault, right?

Is me messing with the radio and the no start issue a coincidence, or did I mess with the ignition switch somehow, or is the oil level sensor messing with the ignition switch?

Should I go ahead with getting the oil level sensor replaced, or try replacing the ignition switch first since it's much cheaper?

Thanks again.

Intermittent No Start (No Crank, No Click) 2004 BMW Z4

Posted: Thu Oct 19, 2017 7:00 am
by srhutch
Get yourself an ignition switch ready. It might be fine now, but unless they changed it the symptoms will return. For a tenner and ten minutes it has to be the first thing to change.

Intermittent No Start (No Crank, No Click) 2004 BMW Z4

Posted: Thu Oct 19, 2017 7:29 am
by ph001
Change that switch and all your problems will disappear

Intermittent No Start (No Crank, No Click) 2004 BMW Z4

Posted: Sat Dec 02, 2017 7:31 pm
by bluepain
Having simalar problem with startnig intermittently , can you guys tell me about the switch is, its wareabouts , and where to get one please.
Is the switch on the stering colum or in with the ecu box under hood....
Cheers all

Intermittent No Start (No Crank, No Click) 2004 BMW Z4

Posted: Tue Dec 05, 2017 11:32 am
by ph001
bluepain wrote: Sat Dec 02, 2017 7:31 pm Having simalar problem with startnig intermittently , can you guys tell me about the switch is, its wareabouts , and where to get one please.
Is the switch on the stering colum or in with the ecu box under hood....
Cheers all
It's on the end of the ignition switch barrel assembly... (no.3) on this diagram.

If not that then starter solenoid could be stuck (the OP had already replaced starter though).
ignition switch.jpg
ignition switch.jpg (68.32 KiB) Viewed 7818 times

Intermittent No Start (No Crank, No Click) 2004 BMW Z4

Posted: Tue Dec 05, 2017 2:42 pm
by srhutch
bluepain wrote: Sat Dec 02, 2017 7:31 pm Having simalar problem with startnig intermittently , can you guys tell me about the switch is, its wareabouts , and where to get one please.
Is the switch on the stering colum or in with the ecu box under hood....
Cheers all
Here you go, and where I got mine "Quarry Motors"

https://www.ebay.co.uk/itm/Ignition-Swi ... evYyAjGJDw

Intermittent No Start (No Crank, No Click) 2004 BMW Z4

Posted: Tue Dec 05, 2017 6:18 pm
by bluepain
Cheers guys.
Allready changed starter motor .a right royal pain in the bottom on the 2.0L .so I know its mot that ..
Cheers again guys

Intermittent No Start (No Crank, No Click) 2004 BMW Z4

Posted: Sat Apr 10, 2021 5:48 pm
by Banhambuilt
Bluepain

Did you ever sort this?
I’m having the same codes 0027a4 and 0027c3
Cheers