soarerdd

hey matt,
my car lost all power a few days ago. Wont even recognize the key going in the ignition. no headlights, no cluster, no stereo, no door doom switches. Complete dead. Battery is new and took it in the recharge and they said its a fully charged battery.

Any idea? last time it worked before this i was driving normally, parked in front of my house and never to turn on again next time i wanted to start

ming15237

iTrader: (3)

I have heard some bad advice before on these forums, but this is plain pathetic! First rule of any diagnosis is to check if you have power and grounds! DAH! Instead you want some poor college kid to throw 100+ dollars at something in hopes that your idea is the problem! I got a better idea, you can bet him its the ecm, if it's not the problem the only person out the money is YOU!!
To the OP, if you have no power to the ecm again i.e. see no check engine lamp, you need to check all the fuses, if none are blown, the next thing to check is if you have spark, then fuel pressure. Engines are fairly simple, they need thre things to start, spark, air, and fuel. Let us know what you find, and avoid the simple people who tell you to throw money at it!

miraluna

iTrader: (2)

Because your car is an OBD1 you will have to pull your own codes. To do this you will need to find your diagnostic box in your car (either at drivers kick panel or under hood), use a paper clip to insert in the hole for TE1 and put the other side in E1. Turn the car on ( don't start it) and count the amount of times your CEL flashes. This corresponds to your CEL code.

Do a search on it and you will get a step by step.

Hope this helps,

1SICSC4

Really man? Have your read the whole thread? If you did you would see that its painfully obvious that ecu is bad. If you turn your car in the on position and all your dash lights up and you have no CEL coming on then you have a bad ecu(or missing bulb). Anyways the ecu was not my first recommendation. I said to first check to see if the car is throwing coded and gave detailed instructions on how to do this in post #2. I also said that his codes are probably 14 and 15 for the ignition signal.The only bad recommendations are coming from people like you that are telling this kid to search over his entire electrical system to find a problem thats not even there. Now this kid is without a car for almost a week. ECU's go bad in our cars its kinda a common problem. I'm not trying to sell the kid anything and taking my advice will only get him back on the road. Anyways if $100 is that big of a deal for you than maybe you should get out of the Lexus game and stick with cheep cars. Just a thought.

1SICSC4

Now that sounds like a wiring or ground issue. Is your car lowered and if so did you relocate your harness in your tire well? Check all your connections fuses and grounds.

No offence man but this sounds like it is going to be a headache for you. I wish you the best of luck and I'm sorry I couldn't be more help.

1SICSC4

This was explained in detail on post #2

ming15237

iTrader: (3)

Well since you brought it up here is your quote, " FYI don't get a ecu form a junk yard chances those ecus are the reason the car is in the yard. If you need one I know a guy that sells them for $150." Since you got all the bucks maybe you can help a "Poor college kid" out.. you know since you are all rich and all...Or is that $150.00 go right to you?
Anybody who calls themselves a "auto technician" who replaces parts, instead of diagnosing the issue, is EXACTLY THAT a parts replacer, NOT a technician! A Tech examines the vehicle, and it's sub systems, ALWAYS properly verifying power supplies and grounds, Remember these systems need BOTH to operate. So that being said put your money where you rather large ego resides and give the poor kid $150.00, it's really nothing to you... we already know. OP you may want to examine 1sicsc4's previous post, begins to sound like a parrot always saying it's the ecm...

To the OP, if you need a wiring schematic let me know I will email it to you, and help you diagnose this issue.

1SICSC4

The problem is diagnosed. I'm someone who likes my car to run rather than look at it and not drive it but maybe thats just me. Anyway you drive a lx450 what do you know about a sc400. The thing about not getting an ecu from a yard is just sound advice. You can get it off ebay or I'm sure someone on the forum has a few to sell but not me.

Here if you want schematic let me know I have the factory service manuals for his car being that I own one and all. I can give you whatever you want to help him but when it comes down to it you will see that in the end I will be right.

Ming thank you for the fun debate and I'm going to enjoy seeing how this turns out.

GoldSc400: please try to pull codes and to further diagnosis your problem Please make sure your are getting fuel and spark. You can check both sides of your ignition system by the ignition wires on the driver side of the motor. Please get back to me so we can get to the bottom of this. I'm excited to see what the answer is. I will help you do every free diagnosis possible if you would like.

ming15237

iTrader: (3)

First bit of sound advice I have heard from you... Check fuel and spark first! P.S. who am I? I am a ASE Master tech with over 25 years of experience. I do indeed own a LX450 TRD supercharged by me, I also own a TRD supercharged (also by me) 4runner, as well as a 2008 Lexus ISF... That is who I am.. Now does that make me any better than you or the OP... NOPE... Just a little more experienced than some guy who is willing to throw parts at a car with someone elses money in hopes it will be fixed... a Professional Tech ALWAYS diagnosis's the problem before he tries to fix/replace anything! The fact that he had a blown fuse is certainly a real warning sign to me... Buy we will see how this plays out.. Bad fuel pump or shorted wiring? maybe...TBC

goldSC400

Yea thank you, didn't forget you guys just been busy with school and work and trying to get this thing figured out.

The problem has officially been diagnosed as my ECU not working right. Plenty of power going to the unit only 5v of power coming out of it. Since hard wiring the fuel pump and replacing the fuel filter and still not having the check engine light come on I was thinking it was the ECU. Props to SICSC for sticking with that all along, just wanted to test it out before buying a new one.

That said, anyone know where I can get one that I know will be good? Some on Ebay but would rather see if anyone on here would know a better place that wont cost me a grand.

Thanks a bunch everybody, you all were helpful.

1SICSC4

Thanks GoldSC400 it was my pleasure to help. I'm sorry you have been without your car this whole time. I wish the haters would have kept there mouth closed so we could have got this done sooner. My parts guys name is Lonnie Simmons his number for his shop is 813-506-1176. Just tell him you talked to Matt and I told you the ECU was $150. He is kinda hard to talk to because he is a little ghetto but he is good people and will always take care of his customers. Also you can repair your ECU. The part that goes bad is just a capacitor you can solder a new one in and be good to go. Just a thought. Good luck and please let me know if I can do anything else to help!

Nova

iTrader: (21)

fuse dont blow on their own but unwanted resistance could be the culprit

attzor

iTrader: (1)

Post in the parts section first, I bet you can get one for considerably less from another member, I had a 95 sc400 ecu that I couldn't sell for 50$ and I ended up just giving it away.

sevenparro

yes I had the same problem, no start no ignition no sound no click no nothing, after alot of trouble shooting I find out it was the steering column, so i bought a whole steering column froma junk yard (stupid huh)

Well DOES ANYONE KNOW HOW TO REMOVE THE IGNITION FROM THE IGNITION HOUSEING IAM TRYING TO REPLACE THE WHOLE IGNITION COLUMN ANY INFO. WOULD BE HELPFUL THANKS

Phenom300

I'm having the same issue, will you in lighten me on the capacitor that goes bad, and how to repair the ECU, Thanks in advance.