ignition key immediately start

[m0535]

I have a problem with a Mastiff 2007. When the ignition key is turned to ON, the starter immediately begins to crank.

I have checked the start button, and it is working. The two wires from the start button (black and green) are not shorted. The solenoid is functioning properly.

If I disconnect the wire from the control terminal on the solenoid and touch it to start, it works fine.

I am looking for the cause of the problem. Could the ECU be faulty? Lights, blue LED, indicators, etc., are all working.

Thanks for your support.
Dave.

 

[Sven]

Maybe the splined shaft is stuck to the flywheel? Remove the cover to install a starter button to the motor. That cover. See if the shaft is stuck forward. That's the physical (stuck) move minus E thrown at it.

To see if the magnetic field is produced, unhook the cable off the motor. Should arc with key off. No, that would mean phantom battery draw. OP makes no mention of the battery.

Say with key on, a fast tap and see if it sparks? This would show something is engaged between battery and motor.

ECU would code something in the loop is the guess. No codes triggered, not the ECU. But then again, if you had access to an ECU, plug it in and see if it starts normally, then yes.

 

[Mickmorris]

I have a problem with a Mastiff 2007. When the ignition key is turned to ON, the starter immediately begins to crank.

I have checked the start button, and it is working. The two wires from the start button (black and green) are not shorted. The solenoid is functioning properly.

If I disconnect the wire from the control terminal on the solenoid and touch it to start, it works fine.

I am looking for the cause of the problem. Could the ECU be faulty? Lights, blue LED, indicators, etc., are all working.

Thanks for your support.
Dave.

Could be the ignition switch itself. It could be malfunctioning leading to unintended power delivery to the starter motor. Hope you figure it out