Wants to start without the key in it when I put the ground cable on

1993 LEXUS LS 400
260,000 MILES
Avatar
FREDDY CALDWELL
  • MEMBER
  • 2 POSTS
Put in a new starter and everything else, get all done hook up a ground cable the car won't start where are the key in it.
Jul 20, 2019 at 1:25 PM
Advertisement
Avatar
JACOBANDNICKOLAS
  • CERTIFIED EXPERT
  • 110,175 POSTS
Welcome to 2CarPros.

I'm not sure what you are saying. The heading says it tries to start without the key in it when you attach the ground cable. The post says it won't start with the key in it, so I'm not sure what is happening.

If the starter engages when you connect the battery (key out), then you are getting power to the s terminal on the starter. That is the smaller wire. That should only get power when the key is in the start position.

Since you just replaced the starter, are you sure the main cable to the starter direct from the battery (thick one) which is hot all the time isn't touching the wire to the s terminal? I attached a picture of the starting system schematic below and highlighted the two terminals I'm referring to. For the starter to engage, the key must be in the start position which sends power through the starter relay to terminal 50. Once it does, a plunger is electrically pulled to the left and the contact plate allows power to flow via terminal 30 to the starter motor, which then turns the engine. So, if the starter is turning with the key out, power is getting to terminal 50. It could be a short at the starter from the repairs.

Let me know what prompted you to replace the starter.

Joe
Jul 20, 2019 at 11:02 PM
Avatar
FREDDY CALDWELL
  • MEMBER
  • 2 POSTS
Yes, it's trying to start when I put the battery cable on negative without the key in it. so I took starter trigger loose spray and clean it real good. what you backup and stop doing and the next day start it again. that's where I'm at.

Thank you for your email it's trying to start without the key in won't start I don't know how that got in there so anyway I'm working on a friend's Lexus for almost a year now starter then timing belt water pump thermostat spark plugs wires valve cover gasket and new fuel injectors
Jul 21, 2019 at 12:38 AM
Advertisement
Avatar
STRAILER
  • CERTIFIED EXPERT
  • 53,854 POSTS
Can you turn the key to the on position without cranking the engine over to see if you hear the pump in the tank?

Here is a guide that should help:

https://www.2carpros.com/articles/car-cranks-but-wont-start

Please run down this guide and report back.
Jul 23, 2019 at 2:36 PM
Avatar
JIS001
  • CERTIFIED EXPERT
  • 3,412 POSTS
If it is a remanufactured starter from a parts stores then the starter itself will most likely be defective. I would recommend you exchange the starter and get back to us if it solved the problem or not.

Had a co worker trying to help a friend with s starter and same thing. As soon as he hooked up the ground the engine started cranking. It had an internal short.

This is how I see it in my opinion. If it did not do it before you installed the new part then the new part is defective. You just need to back track.
Aug 3, 2019 at 10:39 PM