enigma94

iTrader: (1)

I went to go to work today and started my car and it started up fine. After pulling out of my driveway I realized I had forgot something inside so I pulled back in and shut the car off. When I came back out and tried to start the car I got nothing. Tried it a couple times and everything would work fine, steering wheel would adjust, gauges would reset and all that but it would not crank over at all. I turned the headlights on to see if they were dim indicating a battery issue but they were as bright as they usually are. I checked the battery connectors and they were tight. I also got out, locked the door with the key, unlocked it and tried it again and nothing.

The same thing happened to me 2 weeks ago when I forgot a light on and the battery died and it would not turn over after jump starting it. After several tries it finally turned over and haven't had an issue till today.

I did notice what sounded to be a relay switching back and forth when I would initially try to crack the car over today.

So I'm wondering could this be a bad relay?
My key has been broke and glued back together, could there be an issue with the transponder chip killing the ignition?

My mechanic is out for the holidays till after the first and I can't afford to take it to a random shop so any input on what it could be or what to try would be appreciated!

LScowboyLS

all of the things you mentioned could be the issue, as well as the starter solenoid, or even a bad ground or bad battery connections, ECU issue, neutral safety switch, or a fuse link - better hope it's not the starter or starter solenoid, very expensive on the labor!

PureDrifter

iTrader: (10)

if it's a transponder issue the car would turn over and not start (fuel kill).

Check your battery grounds and have the battery and alternator tested.

RA40

iTrader: (6)

How many miles on car?

SaleenS7

Do you get a 'click' sound when you go to start the car? Same thing happened to me when I ran my battery down after detailing it. It wouldn't start even with a jump, but later that night I was able to start it. Have your battery properly recharged overnight. It may be very well be the culprit.

Some very good points are covered in this thread about battery, maybe it will help you.
https://www.clublexus.com/forums/ls4...car-today.html

Yamae

"No crank over at all" is not so much complicated since it is not related to the ECU. It's simply because of the battery 12V not supplied or the starter motor itself failed. I hope your starter motor not failed yet. The battery 12V is supplied via 3 different routes as is shown below with colored lines.



One is directly from the battery to the starter solenoid contact.
The second one is via 3 components such as 80A Main fuse, 40A Starter fuse and Starter Relay.
The third line is to drive the Starter relay. This is coming from the Ignition switch IG2 to 7.5A Starter fuse, then to Neutral Switch and Starter relay coil. This line also goes to the ECU to start the fuel pump and to ignite. Your problem is the intermittent no crank over and this is nothing to do with the ECU just no 12V supply to one of those 3 lines.

Of course all of those lines go to the ground / chassis. All you need is to check those. I suggest you to check fuses first. If they are OK check the Starter Relay or ground connections.

enigma94

iTrader: (1)

Got in touch with my mechanic and he seems to think its the battery as he said the same, if it were a transponder issue it would still crank over.

I cleaned the terminals last night to no avail, but after sitting the whole day it seemed the battery was drained/low so im thinking thats the culprit. Going to buy a new one and see if that fixes it.

156k on the car

I dont get the normal starter click, the only click i can hear is a faint sound of a relay switching back and forth very quickly upon first trying to start it then nothing after the first try. I do believe its the battery so im going to change that and go from there.

Thanks for all the feedback guys! I'll let you know how it goes after I get the new battery in.

enigma94

iTrader: (1)

So before I decided to go replace the battery I jump started it and it started right up after leaving the cables on for a few minutes. Still will probably replace the battery since it looks to be a couple years old and is obviously not holding a charge very well. I'm hoping my alternator isnt going out since my PS pump is leaking and dripping down on it. Going to have to fix that asap.