BrakeTime

Hi everyone,

the other day i was doing a timing belt service on my 01 IS300, and in the middle of the job I had to leave for work. I also had to reconnect the neg. battery terminal in order to engage the alarm system. The next morning i resumed the repairs and totally forgot to redisconnect the neg. terminal. This was brought to my attention when the wires on the alternator touch the car frame and a big spark was emitted. I didn't really paid to much attention to it until the job was done and i attempted to start the car.

There is no power to the car, but nothing else comes on. No power to dash radio, power seats, alarm doesnt work. Can't even lock the doors from the door panel. Crank but won't turn over. All fuses are good, especially the critical ones like ecu, odb, iga, start, etc.

I did notice that it will only unlock from pressing the "unlock" button the master key.

Has anybody experience this issue or have heard of a such problem. Your time and knowledge will be much appreciated. Please help!!!!

Thanks a bunch!!!

bagwell

there is a specific 1st gen IS300 forum - mods need to move this to https://www.clublexus.com/forums/is-...2001-2005-166/

lexusfan1

yup you can ask them! They will know

BrakeTime

Thanks Guys!!! I really do appreciate it.

jadu

iTrader: (42)

you should start by double checking the fuses. There is a main fuse that will blow if you inadvertently mix up batt plus and minus. I would start there. Good luck.

BrakeTime

Would you be talking about the one I circled in the attached Pic?

jadu

iTrader: (42)

Thank you for that diagram. Double check that but I believe the fuse that may have blown is the 120A Alternator fuse. That only makes sense because of the spark that you saw in your description. good luck

BrakeTime

Thanks Jadu you are right. It was the Alternator fuse. The car is fully power now. But it still wont turn over. Every time I try to start it, it just makes a thud noise. I don't believe starter issue. Do u have any other suggestions?

jadu

iTrader: (42)

Glad that you've got power once again. Let's bump this so someone else can chime in. I'd double check some simple things like the other fuses in that diagram or if the battery has good charge

phoenix19l

I just ran into this exact same scenario in my IS300. The first issue was the lack of electrical power inside the vehicle. This was solved via the Alternator fuse. Apparently the Alternator fuse is a primary fuse for most of the cabin features.

Your second issue with the "thud" is somewhat vague. When you put the key in the ignition and turn it to run, right before starter actuation, is everything normal? if yes, what exactly happens once you turn the key to engage the starter? does the motor spin freely? if not, is this where you are experiencing the "thud"? If you are experiencing the "thud" at this point in time and the motor does not spin over, or spins very weakly, you can go ahead and assume your battery is the culprit (possibly alternator as well, but we will get to that later). these are symptoms of a weak battery that does not have the cranking amps to activate the starter. Charge the battery or jump start it. If the vehicle does have sufficient power and your battery is not weak, but the motor does not spin freely and just a thud is present, I would assume the starter solenoid is going out. In which case, take a long wooden dowel and gently tap on the solenoid as you attempt to start it. It will free up the solenoid from dust and debris generated over the years and may allow it to engage the starter once again. If you are still experiencing issues with the starting of the car, message me on here and I will give you my cell number and I can help you isolate it over the phone if needed.

Being that your alternator fuse did blow, and you drove it afterwards, the battery was not able to charge and the car was running strictly off of the battery. This will kill a battery very quickly.

If you have a multimeter or a volt meter with amperage capability, this will help with the troubleshooting process if the above statements do not fix it. Good luck.

BrakeTime

Hi Phoenix19,

Thanks for your time and help. I just got back in town last night and finally will have the time to attempt what you are suggesting. To answer your question, yes everything is normal right before the starter actuation. Alarm system operates normal too. I do notice that all the interior lights gets dim and the dash lights shuts completely off every time i try to start the car.
The "thud" noise sounds more like the engine is getting some kind of resistant while trying to turn over.

I will try to attempt what you suggested and give you an update later today. If no success I will see if I can post a small video clip so you can get a better understanding of whats going on when I try to start the vehicle.

Thanks!!!

phoenix19l

How did the last attempt go?

BrakeTime

Happy weekend!!!

Ok so I think I know what the "infamous" thud sound I'm referring to. After hours of trying to wonder why it won't crank. Dbl checked everything and everything is where its suppose to be, so I decided to hand crank the engine. Made sure all the timing marks on the crankshaft pulley, exhaust, and intake gears all lined up. And they do. From that position, I am able to hand crank it until right before the I hit the 2nd timing mark and it just stops. Figured compression was building up in the cylinders creating more resistance to hand crank, so I used a long breaker bar to hand crank and it still won't budge. I have a feeling that the pistons are hitting the valves. I don't know how it would be possible since all the timing marks lined up. And I have successfully done this type of repair on this type of car multiple times and this is the 1st time I have encounter this problem. What do you think????

cjstrick98

Changed this fuse and got mine to crank. Just need to get it running now!