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Discussion Starter #1 (Edited)
My car has 86k and the SZL recall was performed way back at 10,000 miles. My motor and accessories only have ~27k on them with the battery being ~6 months old, and registered.

Intermittently in the past month, in the morning starting it for work, the car drags and acts like it barely wants to start, then I get the Servotronic error and the wheel barely turns. I shut it off, let it sit for a bit, then then it fire up just fine. It's more likely to happen if they car has been sitting for at least 24 hours. I've never seen that error while running errands, etc.

Tonight I was messing with INPA for 20 min with the ignition ON to pull some codes. After I went to start it after disconnecting the laptop, it really dragged on starting, then an ABS code popped up as well as the Servotronic. I'm wondering if the SZL is going bad and possibly not letting the car go to sleep and thus draining the battery? I had driven it for a bit earlier in the afternoon so the battery should have been good and charged. The dragging is concerning :dunno:

Here are some codes

ZGM 93BD
SZL 951A and C9AA
PGS A08C (I couldn't find anything on this one)
HUD A4F2
CAS A114 and A0B2. My CA works pretty well but I have a hard time locking it with the driver's handle.
 

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Discussion Starter #2 (Edited)
Sure enough, dead as a doornail this morning. I thought I was hearing things but last night around midnight I heard the SMG pump trying to prime twice within 15 minutes, with a real weak "wrrrrrrrrrrrr" sound. Perhaps a load test on the battery would be a good place to start?

Edit: Just got it jumped off and am reading 13.8 at idle, I thought normal charging voltage was supposed to be well into the 14s, can anyone confirm?
 

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Discussion Starter #3
Bump..for the next 11 days it never did it again. Then I went offshore on the 14th, and my wife drives the car every once in awhile. She said it had been fine up until yesterday when it happened again. So does anyone know, can a bad SZL module cause the battery to drain and a lagging start, or could something else be draining the battery and causing the SZL error? Which came first, the chicken or the egg? ouich
 

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Discussion Starter #4
Update...car had been sitting for a few days, came home from offshore and found it dead as a doornail. Charged it, started it, got another servotronic error. Restart and it's fine. Went appliance shopping with the wife, and on restart, got an ABS error (drive moderately, no hard braking, etc). Then went to Lowe's, restarted just fine. Went to Home Depot, tried to restart and got nothing. After repeatedly hitting the start button, the dash lights start going crazy and it finally catches. Seems like something is shorting out. The steering column didn't come down as usual, and after hitting the switch down, it stayed still for a few seconds, then moved. I hit forward, and it moved up, so that's obviously screwed up. I'm not familiar with the guts of this steering column, is there a single master electronics switch in there, or different modules for different functions?
 

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Discussion Starter #7
Turns out it was a crap battery even though it was almost brand new. I got it at Advance Auto. They did their dumb little test and it came back as good, but after 10 minutes I convinced them to swap it out and it's been peachy ever since. No more SZL, no more dragging start, fires right up like new :)
 

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I think this is what I have... I have quite a few random codes showing atm. Going into the dealers in a week so hopefully then that'll be it.
I didn't realise until awhile ago how huge the effect on not having a good battery had on these cars.
 

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Discussion Starter #9
Search for "voltage regulator" as well, which is a common failure and can cause all kinds of random errors. You'll find many threads talking about it.
 

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Discussion Starter #10
Wow, you cursed me man...on Christmas Eve afternoon I went to do some shopping, and sure enough, dragggging start and servotronic error when I left. :1zhelp:. Restarted, error cleared, and made it to Hobby Lobby. When leaving, it took me a few restarts for the servo error to clear again and made it home. Then the damn thing wouldn't even restart without my jumper pack. :Thumbdown: I left my multimeter hooked up after turning the car off, and the battery discharged to about 10.8 V :1zhelp:. I swapped in my Cobra battery, tried the test again, and it only discharged to about 11.9 after shut off, then crept back up into the 12s after the car went to sleep. Restarted just fine, no errors.

So, DO NOT buy the AGM battery from Advance Auto for our cars. 2 of the same failures in 14 months, so I got a refund and installed the H8-AGM from Autozone. Fires up in 1/2 second now :2:
 

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Sorry to hear that! what battery isit that Bmw put in? I had mine replaced by them 2 years ago and has Bmw written on the battery, and I think it may just be the AGM battery as I can't see any marking of 'H8'. You think that the stock battery is no good?
 

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