FuzzyMD

hello, I tried to install the SRT intake with ECU on my 98GS4 this Sunday

After I installed the SRT ECU, and start up the GS400, the following lights went on

Brake, VSC, ABS, VSC Off

Then I removed SRT ECU and reversed the wiring back to stock, then I started it up, I still have the 4 lights

And the biggest problem is; in addition to the “Brake” light , I have no brakes, I mean the brakes now has no electric/hydraulic assist when I try to test drive it in very low speed, I have to applied full force to the brake pedal just to slow down in low speed, it sort of like you try to brake a car without the car being started, I have checked the brake fluid just in case, and it's full, and the brake pads are fairly new

And then about 10-20 second after the car is started, there’s came a very high patch noise (it is not mechincal or metal noise, it sounds like a warning noise), the noise would not go away until I turn the car off, then as soon as I turn the key to the “on” position, the noise came again

I have call SRT, they suggest to check the wire connection and unplug the battery to clear the codes, the tech support said I may have to go to a shop with Lexus ECU tool to clear the codes

Anyone have any similar experience especially about the brake problem and the high patch noise?

The one thing that caught my mind when I trying to think back is that , right after the initial installation was completed, I tried to start the car without any success , then I saw the first socket from the left of the ECU was loosen (I unplugged all sockets before the installation to give myself little more room to work), I then push the socket back in without first disconnect the battery, would that cause of my problems?

Sorry for the long post, any help would be greatly appreciated

chuckb

did you reset the ecu since you put everything back to stock?

if not, disconnect the battery for a half hour or so.

PHML

iTrader: (33)

did u remove the negative battery cable b4 starting the install?

double check and triple check the connections. I must have checked my connections 20 times before even thinking of starting up the car. And lucky I did....cuz I found a mistake and connected the wrong wire.

Also, did you take soder and tape up the connections so that it does not touch any other exposed wires?

Dx3

iTrader: (13)

If you disconnected some things, I would verify that you re-connected everything and didn't accidentally pull something out. Installing the SRT has absolutely no correlation to the brakes - unless of course you shorted something out??

I would try to get my hands on an OBD2 scanner to check and delete your codes.

Also, to start with - remove the ECU-B fuse from under the hood for AT LEAST 1 HOUR. I had removed mine for 45 minutes one time which wasn't enough.

Sorry I can't be of anymore help.

Let us know what you find out. Good Luck,
Jonny

FuzzyMD

thanks for you guys quick reply

+did you reset the ecu since you put everything back to stock?
- yes I did, by disconnectting the neg. terminal of the battery for at least an hour


+ did u remove the negative battery cable b4 starting the install?
Yes I did, but the careless thing I did was, after the inital installation, I re-connected the neg. terminal back, then car won;'t start, then I found that I didn't fully plug in the first socket of the ECU(from the left) so I push it back in without first disconnecting the neg. terminal

+ did you take solder and tape up the connections so that it does not touch any other exposed wires?
- I did tape it out, pretty sure nothing touching exposed wires, I will double-check tomorrow morning


+If you disconnected some things, I would verify that you re-connected everything and didn't accidentally pull something out. Installing the SRT has absolutely no correlation to the brakes - unless of course you shorted something out??
- good point, I will double check on this tomorrow


+I would try to get my hands on an OBD2 scanner to check and delete your codes.
- will do that, does it need a special OBD2 for Lexus? would the place like AutoZone one work with the GS4?

+ Also, to start with - remove the ECU-B fuse from under the hood for AT LEAST 1 HOUR. I had removed mine for 45 minutes one time which wasn't enough.
- Jonny, is the fuse box that right below the Battery? I have tried to open it, so many fuse s in there, which one is ECU-B fuse ?

DaveGS4

iTrader: (2)

Yes. After you take off the cover if you flip it over and look inside the lid there is a fuse map that will show you where the right one is

Dx3

iTrader: (13)

Hey,

Yes, you can do it at autozone - they have the appropriate connector. I just worry about you driving there without suitable brakes.

As Dave said, there is a code on the back. It is the very first 20a fuse at the end I believe.

Jonny

bmgs400

These two comments look suspicious.
- As you know, never hot plug a connector. You may have blown the ECU, or it may need reprogramming.
- SRT advises against using tape...soldered connection is recommended. You have a very poor connection with very little surface-to-surface area actually making contact when you use tape. Good hot solder flow allows for maximum conductivity over all stranded wire (or solid) wire surfaces.

GSoup

here ya go.......hope this helps

FuzzyMD

thanks for the responses guys

+ As you know, never hot plug a connector. You may have blown the ECU, or it may need reprogramming.
- agree, this is the only thing in my mind that could have done damage to the ECU


+ SRT advises against using tape...soldered connection is recommended. You have a very poor connection with very little surface-to-surface area actually making contact when you use tape. Good hot solder flow allows for maximum conductivity over all stranded wire (or solid) wire surfaces.
- I did use solder all the time


Jonny, SRT and my EE friend all point out that my symtons sounds like something get shorted out, I will check it this weekend, rainning outside

GSoup

i was actually thinking the same thing you may have shorted out your ecu

bmgs400

Fuzzy...have you found the cause to, and remedied, your problem?

FuzzyMD

I don't have a garage so need sun-light to work on the car, I plan to work on it tomorrow morning, it seems like everything coming down to either damaged engine ECU or wire/s got shortern, I have already tried eveything else the memebers here suggested

so tomorrow I am going to

1) check the solders and wires with my EE friend

2) If 1) deosn't fix it then drive the car to AutoZone for ECU reset using OBD2 tool

3) if 2) doesn't fix the problem then I would have to just order a used ECU and pray



thanks for asking thou, I will keep you guys posted

bmgs400

Good luck.

I'm planning on the same mod too in the next few months. Where did you get the SRT intake w/ECU?

GSoup

does anyone you know own a gs4.?. If so, try swapping the ecu and see if your car has the same issuethat is the issue before you order a new one.

i installed my srt and ecu and didn't have one problem...