What is the problem if a BMW 320i won't start and has no spark at all?

Answer 1

1. It sounds like you may have a Flat Battery

2. Dead Crankshaft Sensor

3. Blown Starter Fuse or Relay

4. Dead Immobiliser

5. Factory ground cable???

Using a test light, clip check for ground at coil (-). If ground is present with the key in the "on" position but goes away when cranking, it is most likely that the anti-theft system (imobilzer) is taking ground away from the coil to prevent the car from being started. If this is the case, go to the alarm module (below the dash to the left of the steering wheel) and locate the large connector for it (leave it plugged in). If you jump wire the upper and lower far right wires, the car should start. If the car now starts, you have a fault in the anti-theft circuit.

(Factory Ground Cable)

I had my 1982 BMW 320i for 17 years and the last few years intermittently I would turn the key and nothing at all , Just would not start,. It could be the very first thing in the morning or after coming out of an hours shopping at the market. Wouldn't make any sound at all when I would try to start it. And of course It would never happen when it sat at the mechanics. I was so fed up I had some time and drove to my long time friends shop, and low and be hold with gods help I'm sure...It happened! After testing a few things under the hood he asked me to step out of my car and raised it on the rack, he walked under the rear wheel and said yep here's the problem...The Factory Ground Cable was lose and full of dirt and grease and was not grounding. He cleaned all the dirt and grime off and tightened the bolt and it never happened again. Mystery solved.