My mercedes 300E does not start, the crankshaft won't try to turn, the
waterpump has just broke down few days before, but now it just does
not start at all... wonder if when over heated the relay wouldnt work..
On May 19, 7:36 am, email@example.com wrote:
When you say that crankshaft won't try to turn, do you then mean that
starter solenoid does not activate (a noticable click) and that
starter motor does not try to drive the crankshaft?
And is it with automatic or manual transmission?
Anyway, the voltage to the starter solenoid has a very simple path:
Through "start" position of the ignition key and through the starter
lockout switch at the gearbox (if automatic transmission.. it will
only start in P or N).
If the starter motor tries to drive the crankshaft without succes, you
have a serious problem in the engine.
If the solenoid does not activate, you should troubleshoot the
described path. The starter lockout switch is a probable cause (are
you sure it is in P or N?). Also if you have antitheft starter
lockout, it would be in this path. It could also be the "30 circuit"
fuse (I don't know the fuse number for your model), but then there
would be no lights in instrument panel lamps when ignition key is in
If the solenoid activates, but the starter motor does not try to drive
the crankshaft, the problem is the starter motor (or the battery line
We need more accurate information.
1. Is the battery good? If no, charge (or change) it first.
2. If battery is good, is there clicking sound from the starter solenoid
when trying to start? If no, solenoid (or cables to it) is bad.
3. If yes, does the starter make noise trying to turn? If no, starter
(or the battery cable to it) is bad.
3. If starter does make short period of noise trying to turn but the
crankshaft does not. It might be engine internal.
4. Was the car driven with a broken water pump? How hot and how long
was the overheat? Was the overheat the last time this engine ran? If
yes, there is serious problem.
5. There is a very remote chance the engine is water locked, meaning the
head gasket broke and coolant leaked into the cylinder. Liquid filled
cylinder cannot be compressed hence crankshaft won't turn. To check
water lock, remove all spark plugs to check if liquid pouring from
cylinder. But since the overheat just happened, I highly suspect
victoraul firstname.lastname@example.org wrote:
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