Urgent Help! Starter Motor won't stop turning, even with key out

[trd_st184]

Hey everyone,

I have a Toyota MR2 SW20 3sge

I just went to go for a drive and heard that my starter motor wouldn't switch off.

I am urgently looking for any help or assistance. If anyone has an ignition switch or if this has happened to anyone?

Your assistance would be hugely appreciated. Car is currently broken down.

I tried taking out the key completely and the car would keep cranking.

Anyone who may have experienced this, I would be hugely grateful. I even removed the signal wire to the starter motor and it is still cranking over for me.

I am really appreciative of any help.

Is there a starter motor fuse somewhere on the car? someone told me it could be the starter motor shorting inside?

In eastern suburbs

0425 823 736

[RA35GT]

The starter motor usually does not have a fuse.

If the signal wire is off and it still turns then its likely that the solenoid itself is stuck. Try whacking it.

Permanent solution, is to remove the starter and disassemble the solenoid bit, give it a birthday. (clean it up, new brushes if required).

[trd_st184]

So even with the key out and the signal wire is out, would a starter motor still be able to start on its own accord?

I am guessing the ignition barrel is fine because when the ignition is on, the dash lights come up fine, and switch off when I go to the accessories mode.

[banana_socks]

The starter is generally hooked directly to the battery. When the solenoid is engaged (via a relay) it'll connect the actual starter to the battery, and you get cranking. If the solenoid is stuck on, it'll keep cranking.

The actual motor circuit is battery>starter>earth so there is not likely anything shorted there, else you'd be seeing sparks.

+1 to hit it to try and free the solenoid. Else you'll have to remove it. Hopefully that's easy on your engine, though being an MR2 I don't think anything is.

[RA35GT]

Below is the general layout of the starter motor circuit.


What usually happens is when you turn the key to start, the trigger wire is switched to 12V. This energises the solenoid, which in turn causes the plunger to stick out and connect the two red lines, which connects 12V from battery to the motor. (The starter itself is grounded through its body).

Most likely the plunger is jammed out.

[machschnell]

yeah disconnect the battery and then rebuild solenoid or buy new one. should fix the problem . Although once you got sick of the noise a stuck starter makes when the engine is running I am assuming you already disconnected the battery

There is not much to a solenoid as the picture above describes its just a magnet coil and plunger so its probably picked up some gunk in there and jamming home

[RT104GT]

make sure solenoid has not welded on, take the lead off it and measure with ohmeter

[RT40Corona4AGTE]

+1 for stuck/welded solenoid. As others have said, it cant be your ignition barrel as you have removed the trigger wire which the ignition barrel operates.

Let us know what you find. Placing an resistance meter (multimeter on ohms setting) over the solenoid with the lead removed will tell you that it is hard on.

[trd_st184]

Thank you all for your help.

I bought a new starter motor and it works perfectly. I made my vicroads appointment too which I am wrapped about.

Thank you all!