VSC and VSC Off Lights - Limp Mode
05-07-12, 12:02 PM
#211
Pole Position
05-07-12, 12:46 PM
#212
Lead Lap
Thread Starter
05-07-12, 12:49 PM
#213
Lead Lap
Thread Starter
Its been a while - I unplugged the sensor and tested voltages on the wires, I believe there is a +5 and +12 wire...you would literally need to tap into the other 2 wires to see which one is which (using needle-style probes that can break the insulation without leaving a huge hole) then rotate the lever assembly and take note.
if you have a cable running from you gas pedal (and yours should), then you can rotate the lever assembly by hand under the hood.
if you have a cable running from you gas pedal (and yours should), then you can rotate the lever assembly by hand under the hood.
05-10-12, 02:03 PM
#215
Pole Position
Just did my timing belt, water pump, seals, thermostat, etc.
Codes went away for a while, but were present again this morning.
Haven't done the drop voltage test since I don't have needle style probes for my multimeter.
Will try and get that done in the next couple days since I need to change my spark plugs anyway.
I know I looked inside my throttle body and it's filthy, but I don't think a possible sticking throttle would cause the CEL and p1120/1121 codes.
Codes went away for a while, but were present again this morning.
Haven't done the drop voltage test since I don't have needle style probes for my multimeter.
Will try and get that done in the next couple days since I need to change my spark plugs anyway.
I know I looked inside my throttle body and it's filthy, but I don't think a possible sticking throttle would cause the CEL and p1120/1121 codes.
05-10-12, 02:24 PM
#216
Ugh,
I have this same problem, codes 1120, and 1121. I've already replaced the APPS. I've replaced the ECU, got the key reprogrammed, but I cannot find a wiring diagram for the life of me. I know how to use a multimeter, but I just don't know the wiring. Can anyone help? I'm totally fed up with this car. I've purchased numerous complete throttle bodies, and finally broke down and brought a brand new APPS, and still nothing.
I have this same problem, codes 1120, and 1121. I've already replaced the APPS. I've replaced the ECU, got the key reprogrammed, but I cannot find a wiring diagram for the life of me. I know how to use a multimeter, but I just don't know the wiring. Can anyone help? I'm totally fed up with this car. I've purchased numerous complete throttle bodies, and finally broke down and brought a brand new APPS, and still nothing.
05-10-12, 04:19 PM
#217
Pole Position
If you changed the APPS and ECU it could be the motor control unit. But then again you said you've purchased numerous throttle bodies. Did you switch out the entire unit including sensors or did you just swap the sensors onto your original throttle body?
05-11-12, 08:40 AM
#219
Lead Lap
Thread Starter
ihiryu: Ok, if you have replaced entire TB, and ECU, then you are left with 3 and only 3 possibilities:
1) The VSC/ABS control module on your master brake cylinder is bad - the signal from the ECU to the TB is processed thru the VSC/ABS so that it can shut down the gas in the event your car is sliding when VSC is active. - In my opinion, this is probable.
2) You have a bad Pin connector, or bad wire (read broken wire or shorted wires) between the TB and the ECU or VSC/ABS unit. There are 3 harnesses to the TB - the TPS, the Motor Control and the APS/Lever Assy - ANY problems in any of the wires or pin connectors will cause a problem.
3) or ALL of the TB's you have are Mechanically faulty as in the throttle valve shaft itself is sticking...Note in my opinion this is highly unlikely but it is possible.
If you have replaced the entire TB and ECU it can be nothing else...its a closed loop circuit.
I think Your going to have to test each wire individually.
1) The VSC/ABS control module on your master brake cylinder is bad - the signal from the ECU to the TB is processed thru the VSC/ABS so that it can shut down the gas in the event your car is sliding when VSC is active. - In my opinion, this is probable.
2) You have a bad Pin connector, or bad wire (read broken wire or shorted wires) between the TB and the ECU or VSC/ABS unit. There are 3 harnesses to the TB - the TPS, the Motor Control and the APS/Lever Assy - ANY problems in any of the wires or pin connectors will cause a problem.
3) or ALL of the TB's you have are Mechanically faulty as in the throttle valve shaft itself is sticking...Note in my opinion this is highly unlikely but it is possible.
If you have replaced the entire TB and ECU it can be nothing else...its a closed loop circuit.
I think Your going to have to test each wire individually.
05-11-12, 09:58 AM
#221
Lead Lap
Thread Starter
I dont unfortunately. I do know there is +5 and +12 volt signals going to the lever assembly.
I recommend doing some intense google searches, Im pretty sure you can find the wiring diag.
There is also a manual on Lexus now, you have to buy it, or you may find a search of some of the diagrams out of it.
Its a frustrating problem for sure, sorry I dont have the Diagrams.
I recommend doing some intense google searches, Im pretty sure you can find the wiring diag.
There is also a manual on Lexus now, you have to buy it, or you may find a search of some of the diagrams out of it.
Its a frustrating problem for sure, sorry I dont have the Diagrams.
05-11-12, 11:34 AM
#222
Lead Lap
Thread Starter
This might help:
Lexus gs300/430 98-05 service manual (it`s a copy of http://bahamutcars.free.fr/workshop/ , OLDer version)
http://rapidshare.com/files/29168405...ice_manual.exe
Lexus gs300/430 98-05 service manual (original cd-version of manual from bahamutcars, NEW)
http://rapidshare.com/files/33266630...ice_manual.zip
Lexus gs300/430 98-05 service manual in pdf.
http://rapidshare.co...S300_manual.pdf
Lexus gs300/430 98-05 wiring diagram
http://rapidshare.com/files/32414362...ng_diagram.rar
Lexus gs300/430 98-05 service manual (it`s a copy of http://bahamutcars.free.fr/workshop/ , OLDer version)
http://rapidshare.com/files/29168405...ice_manual.exe
Lexus gs300/430 98-05 service manual (original cd-version of manual from bahamutcars, NEW)
http://rapidshare.com/files/33266630...ice_manual.zip
Lexus gs300/430 98-05 service manual in pdf.
http://rapidshare.co...S300_manual.pdf
Lexus gs300/430 98-05 wiring diagram
http://rapidshare.com/files/32414362...ng_diagram.rar
05-11-12, 11:38 AM
#223
Pole Position
There's a link to the Lexus manuals on CL.
I've downloaded some of the files, but not any wiring diagrams yet.
If you havent changed the entire throttle body to determine if it's the shaft then you can try that route.
If I come across the wiring diagram I'll be sure to post a link to the files.
Still having the codes issues with my car. Still trying to diagnose my problem. Might go with Tuanville to his mechanic to see if it can get sorted out, but that's not until next week.
I've downloaded some of the files, but not any wiring diagrams yet.
If you havent changed the entire throttle body to determine if it's the shaft then you can try that route.
If I come across the wiring diagram I'll be sure to post a link to the files.
Still having the codes issues with my car. Still trying to diagnose my problem. Might go with Tuanville to his mechanic to see if it can get sorted out, but that's not until next week.
05-11-12, 12:18 PM
#224
So a buddy of mine has an IS300, I put my TB (my TB has the NEW lever assembly) onto his car. Same thing, same codes. I put his TB back onto his car, and disconnected the TPS, and it does the same thing, and even throws the same codes. So for me, it MIGHT actually be the TPS. I've ordered a new TPS from Autozone, it'll be here later today. I'll update this once I get it.
05-11-12, 01:17 PM
#225
Lead Lap
Thread Starter
Ok, so this infers that the TPS on the new TB is bad?
I thought you said you replaced the TPS as well as Lever ASSY at one point? Maybe Im mixing up people?
Thing is...I did the TPS...it fixed my problem for 2 months, then the controller motor went bad. Thats when I went with a 2002 TB onto a 98. It never was the TPS in my case, even though its the code it said.
Im pretty sure Lexus Dealers know this. In fact Im sure of it. They refuse to replace any sensors/controller motor on the TB except the TPS, and instead always say you have to order a $1400 new entire TB. which is Bull. (I called lexus US headquarters and made a complaint..im sure it went nowhere)
No Probs since.
Let us know what ends up permanently fixing your prob...maybe you got a used TB with exact same bad sensors as your old one...would really surprise me. Alternatively, you may have a mechanical problem with the gears/shafts from the motor control to the butterfly throttle valve in both TB's. Its possible, as they shafts ride on bushings which can corrode and cause friction which will then freak the controller motor AND TPS out, because the TPS is the FINAL sensor in the entire array...it reads WHERE the butterfly valve is opening to.
My old Motor controller was the problem, not moving the valve to the correct position, thus causing the TPS to read an incorrect position compared to the lever Assy/APS, which triggered the fail-safe limp mode.
It happened once the car got warmed up usually, then happened more and more often until it stayed in limp mode.
I thought you said you replaced the TPS as well as Lever ASSY at one point? Maybe Im mixing up people?
Thing is...I did the TPS...it fixed my problem for 2 months, then the controller motor went bad. Thats when I went with a 2002 TB onto a 98. It never was the TPS in my case, even though its the code it said.
Im pretty sure Lexus Dealers know this. In fact Im sure of it. They refuse to replace any sensors/controller motor on the TB except the TPS, and instead always say you have to order a $1400 new entire TB. which is Bull. (I called lexus US headquarters and made a complaint..im sure it went nowhere)
No Probs since.
Let us know what ends up permanently fixing your prob...maybe you got a used TB with exact same bad sensors as your old one...would really surprise me. Alternatively, you may have a mechanical problem with the gears/shafts from the motor control to the butterfly throttle valve in both TB's. Its possible, as they shafts ride on bushings which can corrode and cause friction which will then freak the controller motor AND TPS out, because the TPS is the FINAL sensor in the entire array...it reads WHERE the butterfly valve is opening to.
My old Motor controller was the problem, not moving the valve to the correct position, thus causing the TPS to read an incorrect position compared to the lever Assy/APS, which triggered the fail-safe limp mode.
It happened once the car got warmed up usually, then happened more and more often until it stayed in limp mode.
So a buddy of mine has an IS300, I put my TB (my TB has the NEW lever assembly) onto his car. Same thing, same codes. I put his TB back onto his car, and disconnected the TPS, and it does the same thing, and even throws the same codes. So for me, it MIGHT actually be the TPS. I've ordered a new TPS from Autozone, it'll be here later today. I'll update this once I get it.