Hello Club Lexus,

First post on this board but not the first time i have done repairs on our SC.
Our SC has almost 250K miles on it and has been sitting for over a year now doing a multitude of repairs - front lower control arms, starter (damn what a job!!), new leather to front seats, seat tracks, rear control arms (still working on them), trani mount, drive shaft rubbers, pan gaskets, tune up, considering an EGR delete, etc.

I got to a point just the other evening it was time to start it - the starter is fresh (rebuilt) from Napa - the main cable to the starter is freshly revamped - the signal wire has been replaced from the starter to the first connector into the harness (which is now behind the heat shield of the d/s cat) - when I turn the key, everything seems Ok until I hit the start position - then everything in the dash dies, the starter wont engage to spin the motor (I did hear it click once) and stays dead until I turn it off and then try again - happens over and over

The battery tests good and will hold a charge - it's an Advance battery that was new about 2 years ago - terminals have been replaced and cleaned

I'm stumped - i did find a couple of bad fuses that i will be replacing tomorrow and I will also try a known good relay for the original fcty relay that is still there.

Any ideas that I'm not aware of?
This thing is really causing me a major headache - I need to get it back on the road pronto
TIA
Patrick

 

Make sure you replace all the blown fuses, double check your wiring to the starter wouldn't hurt just to be sure. One wire in the wrong place is all it takes. Has your battery been sitting the entire time your car has been down? How was the battery tested? A volt meter or a load tester? A failing battery can give a good reading but not show a dead cell.

 

I'll have to dig further into the harness to see if there is any other issues with the starter signal wire

Yes, the batery has been sitting - it was new about 8 months before the starter gave out and the suspension got hit - I have charged it from time to time - I tested it with both my DMM and an old fashioned style load tester - I made the load tester element start glowing and the gauge never fell below below 12v

I'll post back up once I get the fuses replaced - the 40A fuse in the kick panel was questionable although it appeared normal - there was a hole in the side of the fuse case?

 

Hmm...is the motor seized? When you go to start the car, everything should shut off on the dash. Since the starter draws a lot of power and amps, it turns the dash off. My SC4 has always done it.

 

No, the motor isn't siezed - i can turn it with a wrench and it was running (except for the starting issue) when we put it up - i know the dash goes dark but should only for as long as the starter is turning - once you release the key, the dash will either stay dark or kind of try and light - this is an electrical issue

I did find some of the main fuses (under the hood) quite corroded - I have new ones on order to be in tomorrow morning - we'll see what happens

 

Ok, I didn't change any results with replacing the corroded fuses
They did need to be replaced, but the no start problem is still there

I have been studying the fcty manual schematics and am beginning to traced the entire starting circuit
there is obviously something wrong in the wiring itself

 

Well, I found I have a bad Neutral safety switch
Going to pick one up tomorrow

 

Ok, got te neutral safety switch replaced and adjusted - the old one was definetely bad
But, it didn't get the starter to turn
I'm going to bypass the only device left in the circuit - the theft deterrent box
don't know if this will work or not but I'll post back my results

 

if you can, bypass everything and just hook up a few wires directly to kick the starter on, see if the starter will turn over. that will eliminate if it's the starter or not. since I've had plenty of autozone starters go bad on me after two cranks.

 

I didnt want to bypass anymore -- i have determined there has to be a short -- i have the main engine harness laying across the table right now -- its a mess -