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Discussion Starter #1
I had a bad alternator and my cable was a bit frayed where it connects into the alternator, so I changed both over the weekend. The cable is the heavy gauge one that connects under the passenger floorboard and goes to the starter, alternator and positive terminal in the engine bay. My DVM registers a healty 12.95v on a fully charged battery.
I had removed the positive terminal from the battery before beginning work. The alternator is connected as is the diagnostic wiring. The starter solenoid is also firmly connected.

When I go to turn on the car, all instruments are fine and everything in the car seems to function. Switching the key all the way on does nothing - no click, nothing.

I was wondering if I may have moved anything while tightening the starter motor - a visual inspection does not reveal anything unusual. Is there a way to check to see if the electronic security measures have been tripped or other reason the car may not start?

Thanks in advance.
 

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Discussion Starter #2
Follow up - I removed the plug to the starter and tried a 12v source and the solenoid did not click. I have now removed the starter and will source another. Looks like the solenoid decided to quit - but that is a strange coincidence.
 

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What year ,, how many miles in car please
 

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If the heavy 12V supply to the starter motor is connected properly, you may have disturbed or broken the lighter black wire that energizes the starter solenoid when you select the key to the crank position. Get underneath and check to see if you are getting 12V at the smaller screw terminal on the starter, terminal X6510, when the key is turned to the crank position.

Starter solenoid connector.JPG
 

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Discussion Starter #6
I used an external 12v source to try to actuate the solenoid. It would not, so it appears that the solenoid itself is at issue. As for the age - I am not sure. Car is MY 2001, but it is not clear that the starter is/was original. Based on the low cost of replacements (and ease of that install), I will test the new one manually and then reconnect. I will verify that I get 12v on the connecter 68FB before I button everything together.
 

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Hi Mike, are you getting 12v at the alternator connector/wire? Also make sure things are tight. Loose battery ground cable will cause this. (put in key, lights light up, turn and nothing happens). If you detached the ground cable when you started the project and then just put it back without tightening that 10mm, then its definitely the ground cable.

Additionally, like others mentioned dead fuel pump will have the same symptoms.
 

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What is the current capacity of the 12V source you used on the solenoid? I don't know what the starter requires, but it's possible that the requirement of the solenoid exceeds the source?
 

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Is there any chance you inadvertantly swapped the two smallest leads of the 4 which attach to the starter? If you're not getting voltage I wonder if a fuse is out somewhere. Otherwise doesn't the signal come straight from the DME or maybe via relay? I changed my starter a while back and they seem robust. Even if the solenoid fails to engage the teeth wouldn't it still spin up? I can't imagine it failing coincidently...good luck.
 

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Solenoid is what allows power into the starter at all. So you could have it spinning and not kicking out, but the solenoid has to allow power in. Same power coming in engages the "spin" and the "Kick out".
 

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Discussion Starter #12
The only thing I touched on the starter was big cable lead which I replaced. The small leads were not touched. To activate the solenoid I used a bench 12v DC source with the high current setting, but I did not check amps. To activate I used the plug wires and tried to put 12v across the small terminals. I will have another used starter to test out against. I know the battery lead was sending full voltage to the big cable. I was just trying to activate the solenoid with the bench supply to see if that was the issue.
 

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There is your problem you did not have a ground. The two small terms are not positive and negative. One is positive the other is positive to the ECM fan while the starter is cranking. The path to ground is through the brushes to the body of the starter.
So What you need to do is hook the ground to the body of the starter.
starter.JPG
 

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Discussion Starter #14
I have the whole starter out. I can rig up a ground and try activating using the bench supply and some wires. If that works, my suspicions would be on the signal from the x6510 or the ground of the unit.
 
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