HELP Car won't start

[fastgoat]

I was getting ready to leave for work, but my car wouldn't start this morning. I hit the push-button start and get a single click following by the standard electric whir, but the car will not crank. I tried a new battery but the same issue persists.

Could this be an alternator or starter issue? I did install a new TCU a few days ago as the previous owner had removed it, but car has been fine....

[WrathOTM]

No probably not an alternator, unless the voltage regulator suddenly upped and died. Maybe starter. What is your mileage? Check for codes? Also what are you referring to with TCU?

[Lester]

TCU controls the Bluetooth, antennaes etc.

[Lester]

There are posts of similar problems like this, relating to corroded cables attaching to the starter.

[NewDaddyDee]

Definitely check your ground strap. It’ll cause the problem that’s being described and the car is solidly in the age zone for it to disintegrate.

[Lester]

Another member of this forum recently had a similar problem, it turned out to be the starter cable.
here is his post:
RHERMAN335i How I solved this issue, had me stumped for a while until I went back to basics
________________________________________
Had all of the same issues as your describing and had me stumped as well.. had only purchased the car a couple of months prior and wasn't too happy about having a car that would not start or even try to. Just small clicks when I first turn ignition on coming from throttle body area. Took apart everything to be able to get to starter to have it tested and replaced if necessary. Pulled starter out of the car and tested it myself with jumper cables and turned over ok. Brought to a couple of different part stores to have them bench test and results came back as a working starter... put everything back together and boom. NOTHING... started testing voltages from battery to jump post under the hood. Had good voltage there. Checked voltage from wire leading to starter/alternator as they share the same wire. Boom 12.6... after reassembling everything just to have same results about 6 times I got tired of it and wanted to just see what would happen If I could get engine to start the old fashioned way of jumping power to my solenoid. Made my own little jumping wire to connect from power to jump post and go to my starter solenoid. I wanted to at least see if I could get my engine to crank over. BOOM... Cranked and started easy with no problems just like it was supposed to. Shut car off as everything top side of engine was unplugged and disconnected. Inspected wire feeding from my jump post to the starter and found a couple inches back from the copper ring connector on jump post I had some frayed and messed up little spot of wires underneath the wire wrap/cover... went to my shop and made my own peice of power wire with 2 new connectors for both sides of wire. (Jump post to starter) cut the connector on old wire going from starter to the alternator. Making it two separate wires instead of sharing the same wire. Installed on the car and never had an issue since... saved alot of money by not bringing it to a shop and doing it myself as it took alot of man hours to fix the issue. And saved $280 I believe it was that BMW wanted for that power wire. Hopefully that might help someone
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[fastgoat]

I found a corroded cable that broke off of the terminal. All good now.

Thanks for the responses!

[WilsoN55]

Originally Posted by fastgoat

I found a corroded cable that broke off of the terminal. All good now.

Thanks for the responses!

Looks like starter wire at the firewall?

[fastgoat]

Originally Posted by WilsoN55

Looks like starter wire at the firewall?

Yup, easy and cheap fix.

[WilsoN55]

Originally Posted by fastgoat

Yup, easy and cheap fix.

Yup, it was MY first repair with mine.. tip: 6 months later I had a no start again, it was the engine grounding strap, I saw it was green (corroded, it's braided steel) and thought, I should change that.. well I procrastinated, one day went to get groceries and couldn't restart. $200 tow for a $15 part, buy one, change it now.

Edit: the electronics freakout that happened during the no start.. I thought the car was toast. It didn't sound good, not something I recommend experiencing, lol. Everything was making noises.