BMW Repair: 318i 1998 E46 not starting., electrical voltage, negative terminal

Question
Evan, checked the battery, and it was 11.2 V. Charged the battery, and the motor started, but still the same problem with the central locking. Could it be the engine control unit playing up?
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-----Question-----
Hi Evan,
My BMW started off getting central locking problems, it would lock, but not un-lock apart from the drivers door.
I disconnected the negative terminal on the battery, and left for about 5 mins. then re-connected. Now the engine turns over, but will not start.
Any ideas???

-----Answer-----
Brent, check for spark and fuel. Find out which one is missing.
-Evan

Answer
Brent, I would replace the battery if the voltage is getting that low. Also check the charging system to make sure the alternator is charging the battery and suppling voltage. Make sure the electrical voltage is take care of before tackling other electrical problems.
-Evan