No Crank, No Start after rear interior work

[Will]

Hey guys, thank you for all of your recommendations! When I kept testing, I found that putting the 12V from the fender post to the starter directly let me crank and start the car. To me, this meant that something was wrong with the cable that runs from this post to the starter itself. When I went to unbolt the fender battery terminal nut, there was hidden surface rust under the cable that runs to the starter. After cleaning this up, the car cranked and started just fine. I feel dumb for never checking this, but I'm glad this was ultimately such a simple fix. Make sure your power connections are clean people!!

Thanks for posting your findings and resolution. Glad you found the problem and it's back to normal.

[sapote]

surprisingly not. no hard starts, charging issues etc.

Even on the morning this happened, car started up just fine. Really just a weird coincidence on timing

The rust or oxidation on the cable connection had been going on for a long time so during engine running, heat from extra higher resistance was created for a while.

[ejendow]

You didn't touch the cable connection recently?
I am surprised that the battery didn't have charging issue before, or the fender jumper got very hot and melted plastic box.

surprisingly not. no hard starts, charging issues etc.

Even on the morning this happened, car started up just fine. Really just a weird coincidence on timing

[sapote]

After cleaning this up, the car cranked and started just fine. I feel dumb for never checking this, but I'm glad this was ultimately such a simple fix. Make sure your power connections are clean people!!!

You didn’t touch the cable connection recently?
I am surprised that the battery didn’t have charging issue before, or the fender jumper got very hot and melted plastic box.

[ejendow]

Hey guys, thank you for all of your recommendations! When I kept testing, I found that putting the 12V from the fender post to the starter directly let me crank and start the car. To me, this meant that something was wrong with the cable that runs from this post to the starter itself. When I went to unbolt the fender battery terminal nut, there was hidden surface rust under the cable that runs to the starter. After cleaning this up, the car cranked and started just fine. I feel dumb for never checking this, but I'm glad this was ultimately such a simple fix. Make sure your power connections are clean people!!

[sapote]

voltage at the fender post and battery cables both remain at 12V when cranking. it's only at the starter where the voltage drops to 0V. When I put 12V directly to the starter when cranking, the car starts and idles fine.

There are minimum 2 wires at the starter, so which one dropped to 0v -- fat or skinny one? The fat cable is the same one connected to the fender jumper post which you said it had 12v (not 12 but something around 12.6v; in this case a precise value is important).

[eacmen]

I had the same issue as you are describing about two years ago. For me, it was the crankshaft position sensor. I would note that the front subframe makes the hex bolt, which is located on the firewall side of the engine, extremely difficult to get to. Stubby ball hex keys were the only tool I had that allowed me to replace the sensor absent additional dissasembly on the underside of the vehicle. As others have indicated, your readings point to a solenoid issue, but the CPS is around $40(?) and may resolve your issue. Additionally, INPA provided information about the faulty CPS, so solenoid seems most likely. I wish you the best.

CPS is right near the starter motor as well. So it's one of those “while you're there” items that makes a lot of sense.

[Fresh1179]

I had the same issue as you are describing about two years ago. For me, it was the crankshaft position sensor. I would note that the front subframe makes the hex bolt, which is located on the firewall side of the engine, extremely difficult to get to. Stubby ball hex keys were the only tool I had that allowed me to replace the sensor absent additional dissasembly on the underside of the vehicle. As others have indicated, your readings point to a solenoid issue, but the CPS is around $40(?) and may resolve your issue. Additionally, INPA provided information about the faulty CPS, so solenoid seems most likely. I wish you the best.

[maw1124]

+1 for bad solenoid... you've ruled out seemingly everything else, except maybe crank position sensor. I'd look to throw a CPS at it first, since those are known to go without warning.

maw

[eacmen]

are you referring to the “Starter blocked due to…”? if so those all say No so things look fine there

Hmmm interesting. Since you're hearing the solenoid click but no crank and by jumping voltage to the starter works fine I would then suspect a faulty solenoid. Try tapping lightly on the starter with a light hammer, and see if it fixes it.

[ejendow]

Might be an EWS issue. You have a bmw scanner or INPA? You should be able to log data and it will tell you the reason why it's not starting.

are you referring to the “Starter blocked due to…”? if so those all say No so things look fine there

[eacmen]

Might be an EWS issue. You have a bmw scanner or INPA? You should be able to log data and it will tell you the reason why it's not starting.

[ejendow]

What other work were you doing with all the interior bits removed?

just swapping from grey to black. nothing with the wiring

[ejendow]

Loose big cable.
Chech the voltage at fender post (and the battery cables) when crank

voltage at the fender post and battery cables both remain at 12V when cranking. it's only at the starter where the voltage drops to 0V. When I put 12V directly to the starter when cranking, the car starts and idles fine.

[eacmen]

Hey guys looking to see if anyone has any suggestions for me. Today I had everything out of the rear interior: door panels, seats, shelf, etc. When I wrapped everything up and put the interior back together, the car no longer cranks or starts. I just get a single click.

I first assumed I messed with the fuel pump somehow since I had the bench out but this wasn't the case since I was able to activate it using my schwaben tool.

Is there some wiring that runs to or lives in the rear that I potentially messed up?

What other work were you doing with all the interior bits removed?